Suspect in custody after mall shooting in Burlington, Wash.

Arcan Cetin, a 20-year-old suspected of fatally shooting five people in the Cascade Mall north of Seattle, was arrested about 6:30 p.m. Saturday night in Oak Harbor.

Authorities said the motive for the shooting is unknown.

Key developments: 

RELATED >> PHOTOS: 4 dead in Cascade Mall shooting

Saturday: 8:35 p.m.

Further details were found about Cetin's history. Follow this link to read additional details about Cascade Mall shooting suspect Arcan Cetin.

Follow this link to see a minute-by-minute breakdown of how the story developed, including details of Cetin's arrest.

Saturday: 8:15 p.m.

The suspect in custody has been identified as Arcan Cetin, 20 years old. As part of a court case, Cetin was ordered to undergo a mental health evaluation in August 2015. That was completed by March of this year.

There were also questions in the court file about cannabis use. But a judge said that was not a mental health issue. In May, a judge approved deferred prosecution in that assault case -- meaning Cetin was not convicted -- and he was ordered not to have alcohol or drugs.

As of Aug. 25, 2016, Cetin was in compliance with weekly sessions for mental health counseling, according to court records. He complied with the alcohol assessment, according to those records, and he had a deferred prosecution review for the case scheduled for 2018.

Saturday: 7:30 p.m.

Sgt. Mark Francis with the Washington State Patrol says the gunman was captured tonight by authorities. A press conference will be held tonight. The time will be announced soon. FBI officials in Seattle tweeted that the manhunt was over.

Saturday: 7:20 p.m.

Washington State Patrol officials tweeted that the suspected gunman was in custody. "#Cascademallshooter is in custody," WSP wrote.

Saturday: 6:40 p.m.

A person of interest has been found and taken into custody, Island County Sheriff officials said Saturday evening.

Saturday: 5:20 p.m.

Officials with Skagit County Department of Management say there are no updates. If anyone has information about the suspect, please call police at (360) 428-3211.

Saturday: 4:30 p.m.

A vigil will be held tonight at about 5 p.m. at His Place Church in Burlington in memory of the five people killed last night in Cascade Mall.

Saturday: 3:22 p.m.

An alert was sent to riders on nine Washington State Ferry routes saying law enforcement is looking to help identify the active shooter involved in the Cascade Mall shooting. “If you can help,” the message reads, “please contact 911.” Authorities did not elaborate if they think the shooter took a ferry.

The routes the message were sent to were: Anacortes/Sidney B.C.; Anacortes/San Juan Islands; Port Townsend/Coupeville; Mukilteo/Clinton; Edmonds/Kingston; Seattle/Bainbridge Island; Seattle/Bremerton; Fauntleroy (West Seattle)?Vashon/Southworth; Pt. Defiance/Tahlequah.

The message was sent to ferry subscription message accounts.

Saturday: 2:20 p.m.

The Cascade Mall will remain closed Sunday. The mall plans to reopen Monday for their regular business hours. "In continued support of Friday's victims & their families, we will remain closed on Sunday, returning to our regular hours on Monday 9/26."

Saturday: 1:00 p.m.

Drivers parked on the east side of the mall are being allowed in to pick up their cars. Not yet those parked on the west side.

Saturday: 12:00 p.m.

There are no additional press conferences planned for the day, Skagit County Department of Emergency Management officials said. If there are any serious developments, a conference could be expected. We'll stream all conferences live at kiro7.com.

Saturday: 10:40 a.m.

The gunman is still at large. Anyone with information or tips about the suspect is asked to contact law enforcement at (360) 428-3211.

Four women were killed last night. A man who was seriously injured and taken to Harborview Medical Center passed away overnight. Police said Saturday morning that mall patrons whose cars were left in the parking lot will be able to retrieve their cars later today.

Saturday: 10:00 a.m.

Harborview Medical Center says no other victims are at their hospital from the shooting.

Saturday: 8:30 a.m.

The “whereabouts of the shooter” is unknown, according to authorities in the Saturday morning news conference.

His rifle was recovered at the scene of the mall shooting.  New photos were released during the news conference.

Authorities say they are reconstructing the scene in their investigation, as they process the Macy’s store. The suspect was seen entering the mall without a weapon.

About 10 minutes later the suspect was seen in the store with a rifle. He fired multiple times – hitting victims in age that range from teen to senior. Identification of the victims is not being released as this time. Autopsies still need to be completed.

Michael Knutson, assistant special agent in charge of the Seattle FBI, said at the news conference there was no evidence to point to terrorism.

Saturday: 4:30 a.m.

A fifth person dies from injuries after the mall shooting.

A spokesman for the Skagit County Emergency Operations Center says the unidentified male victim died early Saturday at a Seattle hospital. Four female victims died earlier following the Friday night shooting at the Cascade Mall in Burlington, Washington.

Authorities continue to search for the shooter.

>> Read real-time updates from authorities here.

Friday: 11:50 p.m.

The Cascade Mall tweeted about shooting.

Friday: 11:30 p.m.

New details into KIRO 7 News confirm that the shooter is a lone male shooter. Washington State Patrol says that the shooting was in the makeup department of Macy’s. They do not have details on the motive, and it’s unclear if the shooter has left Skagit County.

Friday: 10:57 p.m.

Cascade Mall in Burlington is 434,000 square feet. Police are 2/3 finished with final clear.

Friday: 10:30 p.m.

FBI joins in the search for the gunman. The FBI says they have no information to suggest additional attacks planned in Washington.

Friday: 10:30 p.m.

FBI joins in the search for the gunman. The FBI says they have no information to suggest additional attacks planned in Washington.

Friday: 10:15 p.m.

Cascade Mall is still considered an active scene.

The mall is an enclosed shopping mall that opened in 1990, according to the mall's website. It features J.C. Penney, TJ Maxx, and Macy's stores, among other stores, restaurants and a movie theater.

Friday: 9:44 p.m.

Washington State Patrol changes number of dead to three people. One person in critical condition.

Residents are asked to stay inside.

Friday: 9:30 p.m.

Gov. Jay Inslee said tragedy had struck the state.

Friday: 9:23 p.m.

People who were inside the Cascade Mall are being taken to His Place Church at in Burlington.

Friday: 9 p.m.

Skagit County Emergency Management releases a photo of the suspected gunman.

A trooper said that the mall had been evacuated and emergency medical personnel were cleared to enter.

Francis said authorities were still doing a "final clear" of the 434,000-square-foot (40,319-square-meter) mall late Friday night. He said 11 search teams and two K9 units were involved.

The parking lot was closed and emergency management officials told people they would be able to retrieve vehicles Saturday, though the mall said it would be closed for the day.

Friday: 8:05 p.m.

Police say that four people died at the mall.

Friday: 7:35 p.m.

Police said they were looking for a Hispanic man wearing black and armed with a "hunting-type" rifle and last seen walking toward Interstate 5. The description of , including that he appeared Hispanic, was based on statements from witnesses, said Givan Kutz, a spokesman for the Skagit County Emergency Operations Center. Residents are told to avoid the mall.

Friday: 7 p.m.

People fled, customers hid in dressing rooms and employees locked the doors of nearby stores after gunshots rang out just after 7 p.m. Friday at the Cascade Mall. A helicopter, search teams and K-9 units scoured the area for a rifle-carrying man.

Tari Caswell told the Skagit Valley Herald she was in the Macy's women's dressing room when she heard "what sounded like four balloons popping."

"Then I heard seven or eight more, and I just stayed quiet in the dressing room because it just didn't feel right. And it got very quiet. And then I heard a lady yelling for help, and a man came and got me and another lady, and we ran out of the store," Caswell told the newspaper.

Information from the Associated Press is included in this report.

Cox Media Group