(HOUSTON) -- The family of a slain Texas medical student who was well-known as an Iranian activist is pleading for the community's help in solving her mysterious death.
Gelareh Bagherzadeh, 30, was driving through her Houston townhouse complex around midnight on Monday when she was shot dead through her car window, just yards away from her home.
At a news conference Wednesday, her family asked for the public's help and mourned the loss of their daughter and sister.
"She's really loving and sweet-hearted," her brother Ali Bagherzadeh said. "I can't think of why anybody would hurt her because she is always being peaceful and just trying to bring peace to this community and society."
Crime Stoppers is offering a $5,000 reward for information leading to an arrest.
Investigators also said that they were looking into a reported 2010 assault against Gelareh Bagherzadeh, but Houston Police Department spokesman Victor Senties said the case did not lead to any further information.
"That was investigated thoroughly and, at this point, it doesn't appear that there were any links," Senties told ABC News. He also confirmed that Bagherzadeh was killed by a single gunshot wound.
Authorities reviewed surveillance footage on Wednesday from one of the nearby townhouses, but the video was inconclusive.
"It does not appear to show anything that would be helpful in identifying a suspect or suspect's vehicle," Senties said. "We still have absolutely no leads on this and we still need the public's assistance.
Though the FBI is aware of the situation, they are not officially involved in the investigation, Houston FBI Special Agent Shauna Dunlap told ABC News Wednesday.
"We are routinely sharing information with the Houston Police Department," Dunlap said. "It doesn't mean we're actually involved. Evidence that a federal law was potentially violated would have to be uncovered for the FBI to get involved."
Bagherzadeh's body was found in her car around 12:30 a.m. Monday when police responded to a report of a shooting in progress.
"When officers arrived, they found a vehicle had run into a garage door at that location with the engine running and tires spinning on the pavement. Ms. Bagherzadeh was found slumped over in the driver's seat," the Houston Police Department said in a statement.
Authorities said nothing appeared to have been stolen from her car. Her cellphone and purse were found inside.
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