Woman says Pittsburg police murdered her son

PITTSBURG, Calif. (KGO) -- In Pittsburg, the mother of a suspect who died in police custody after a struggle says he was murdered. Officials say Humberto Martinez led officers on a chase and fought with them while they tried to arrest him.

EXCLUSIVE: Video shows Pittsburg police chase suspect who died

"I know in my heart they killed him," said Martinez's friend Jeff Wachtler.

Martinez's mother, Jamie Cox, added, "Yeah, they're lying."

Friends and family say the 32-year-old was murdered. Police say he died suddenly after they handcuffed him.

Surveillance video from a neighbor shows when the traffic stop turned into a pursuit. Martinez got out of his car and escaped into a garage with police close behind him. They Tased him, but say it was ineffective. Police say Martinez struggled away from officers in the garage and they followed him in the house.

"Ended up getting into basically a wrestling match with him on the ground in the kitchen for several minutes to the point where our officers were physically exhausted," said Captain Ron Raman.

"Both have their arms around his neck and then they dragged him inside the house and shut the door," Wachtler said.

Wachtler, who was in the garage, gives a different account.

"They dragged him inside the house and closed the door and I could hear them Taser him and beating him the whole time I heard three or four more Tasers," he said.

Police say Martinez resisted arrest and bit an officer in the scuffle. Back up officers arrived.

"As he was handcuffed our officers realized he was not being responsive. All of our officers have a AEDs in their cars so we immediately began providing lifesaving measures," said Wachtler.

Eight minutes later paramedics arrived. Police say Martinez died at the hospital. But his mother, Jamie Cox, doesn't believe that.

"He didn't die in the hospital they beat him up," she said.

"They murdered him right there in my living room," said Wachtler.

Jeff Wachtler says his 6 year old daughter watched it all.

Police say Martinez had a long list of convictions for assault, drugs and other violent crimes.

His family says he was trying to get his life together, had a job, and leaves behind a 15-year-old son and 8-year-daughter.

Three officers are on leave as the district attorney's office investigates the death. Results of an autopsy are expected to reveal why Martinez died.

Click here for more stories and videos about incidents with Tasers.