SAN ANTONIO -- Police said a man was gunned down during a northwest-side home invasion around 1 a.m. Wednesday.

The shooting happened at the Alta Roxbury apartment complex in the 6200 block of Roxbury Drive. The San Antonio Police Department said the victim and his girlfriend were inside at the time of the shooting.

Up to five masked men ransacked the place looking for something, according to police, but it's not clear whether they took anything.

Police said the victim's girlfriend was held at gunpoint as the intruders executed her boyfriend by shooting him multiple times including the back of the head.

A witness saw the men run away from the scene toward Wurzbach Road.

Police said the victim's girlfriend uninjured at the scene.

The victim is in his 20s, according to police, but his identity has not been released.

Investigators said the shooting was not a random act of violence. It appears the crime was targeted.