MIAMI -- A 44-year-old security guard, gunned down at a metrorail station, leaves behind five children and four grandchildren.

Chermaine Joseph-Quetel was shot and killed Sunday at the Dr. Martin Luther King Jr. metrorail station.

Miami-Dade police said patrons at the station, located at 6300 N.W. 27th Ave., saw Joseph-Quetel patrolling the station by herself at about 10:40 p.m. About two minutes later, patrons heard a gunshot and saw a man run away.

Police said Joseph-Quetel, 44, was a five-year veteran of Alanis Security, which contracts with Miami-Dade County to provide security at metrorail stations.

"It's sad because they're here to protect us also," metrorail user Trina Mitchell said.

Family members said that Joseph-Quetel was a good person with no known enemies. She was from the Virgin Islands, where she was a police officer for nine years. Her husband is also a security guard.

Wackenhut Security is offering a $10,000 reward for information leading to an arrest. Crime Stoppers is also offering a $1,000 reward. Anyone with information is asked to call Miami-Dade Crime Stoppers at 305-471-TIPS.