DURHAM — A Durham firefighter charged with robbing eight stores in the last six weeks who tried to kill himself in the Durham County jail Wednesday is in critical condition, the Sheriff’s Office said Thursday morning.

Damon Antonio Quick’s condition was last checked around 8 a.m. According to the sheriff’s office, they have received a report from the hospital that Quick’s vital signs are unstable and not within normal limits. They did not say whether or not Quick is unconscious. He will not be in court at any point today.

Quick, 35, was discovered in his cell by a detention officer conducting security checks at about 1:42 p.m. Detention officers and jail medical staff immediately began first aid while waiting for EMS to arrive, officials said. He was taken to an unnamed hospital, where his condition was unknown.

Quick, whose salary was $40,428, had worked for the Fire Department since 2003. He was fired Wednesday after he was arrested Tuesday night on 43 charges connected to the robberies and jailed under $9 million bail.

“It was a very quick operation,” said Judson Leamon, a West Main Street Dominos’ manager whose store was held up last month.

“He came in the store and held everyone at gunpoint,” Leamon said. “All you could see was his hand; everything else was covered.”

In all cases, the robber wore a Green Goblin style mask, dark clothing and a hoodie and had a gun.

Many of the robberies occurred around closing time for the businesses.

Leamon, whose store was robbed around 10 p.m., said the robber was wearing all black, as well as his trademark mask.

The intruder ordered the four employees to the back of the store and proceeded to take about $100 from the registers. The holdup took about a minute, Leamon said.

There were no customers in the West Main Street store at the time.

“It was almost like he had been watching us,” Leamon said. The store has since added more lights and cameras and will temporarily close one hour early.

Quick is also a suspect in the theft of about $1,200 from individual firefighters, officials said at a news conference Wednesday morning.

“This is not representative of our department,” Fire Chief Bruce Pagan Jr. said. “We have a department who prides itself on being honest and carrying out our duty with pride and integrity. I don’t want the public to think this is a widespread situation.”

Quick resisted arrest Tuesday night and suffered minor injuries, said Durham Police Chief Jose Lopez Sr., who did not elaborate. His police mug shot shows him with a swollen eyelid.

He is charged with:

• 19 counts of second-degree kidnapping

• 11 counts of robbery with a dangerous weapon

• 2 counts of attempted robbery with a dangerous weapon

• 7 counts of assault by pointing a gun

• 2 counts of assault with a deadly weapon, and

• 2 counts of communicating threats

The arrest Tuesday at the Dollar Tree, at 3823 Guess Road, followed a long-term investigation by the Police Department, the Durham County Sheriff’s Office and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

The other robberies occurred:

• May 8 at GameStop, 1804 North Pointe Drive. A man took cash from the business and robbed employees of wallets and phones.

• May 12 at Family Dollar, 1518 S. Miami Blvd. (in Durham County). A man took cash from the business and wallets and phones from employees.

• May 17 at Dollar General, 101 Ganyard Farm Way. A man took cash from the business and robbed employees.

• May 22 at Family Dollar, 2110 N. Roxboro St. A man approached an employee who was emptying trash in the parking lot and then tried unsuccessfully to enter the business, which had been locked. The suspect fled without taking anything.

• May 23 at Dominos, 1209 W. Main St. A man took cash from the business and an employee.

•  May 23 at Captain D’s restaurant, 4300 N. Roxboro Road. A man approached an employee who was taking out the trash and forced him back inside the business at gunpoint. The robber fled with cash.

• June 1 at Dollar Tree, 1515 North Pointe Drive. A man wearing a mask entered the business around 10 p.m., took cash and fled.

Quick had some minor disciplinary problems in the Fire Department, Pagan said but did not specify. “He was very knowledgeable, well-liked by coworkers and easy to get along with,” Pagan said.

The Green Goblin character is an amoral industrialist and the father of Peter Parker’s best friend in the Spiderman comic books and movies.

Kendall: 919-932-8760