A woman whom Houston police described as an activist on behalf of Iranian women's civil rights was found shot dead at the wheel of her car after it crashed into a townhouse garage.

Houston police said the shooting happened around 12:30 a.m. Monday in a posh development near the Galleria.

According to investigators, someone walked up to the passenger's side of 30-year-old Gelareh Bagherzadeh's car and shot her in the head.

Bagherzadeh's body was found inside her running car, detectives said.

"When the officer arrived, the car's tires were still spinning," Officer J.C. Padilla said. "He had to reach in and turn off the motor."

Bagherzadeh's car was found at the back of the town home complex, and police said she had driven past her parents' home near the front of the complex.

"We don't know if she was being followed at the time," Sgt. Richard Bolton said.

Investigators said Bagherzadeh was studying genetic research at M.D. Anderson Cancer Center and was an only child.

Officers said Bagherzadeh's ex-boyfriend was on the phone with her when he heard what may have been the crash and gunshots.

"He said she screamed for her life," said Lorena Lopez, one of Bagherzadeh's close friends. "He heard screeching and he assumed it was a car accident."

The ex-boyfriend was questioned, but is not considered a suspect.

Detectives said they want to speak with her current boyfriend and other friends to try to piece together what happened.

"She has no enemies," Bolton said. "She was a very caring and loving person."

Bagherzadeh was part of Sabaz Houston, a local Iranian organization that supports the green movement against the current Iranian government. Her friends describe her as sweet and smart.

"I can't believe that she's gone," Lopez said. "I can't believe that somebody shot her. I don't know how that's even possible."

Bagherzadeh's purse and cell phone were still inside the car, so investigators are not sure what the motive for the killing may be.

Police have not released any information about possible suspects.

Investigators obtained footage from a neighbor's surveillance system to look to see if anything helpful to their case was caught on camera.