News crews from two television stations were robbed of cameras Thursday morning, and a camera operator was pistol-whipped by a man in a ski mask, as they reported on a homicide at Pier 14 in San Francisco. The mugging — the latest in the Bay Area to target television crews — happened at 6:03 a.m. at the pier along the Embarcadero and was captured in part on the air. KTVU reporter Cara Liu was reporting live when someone ran up and stole camera equipment belonging to KNTV, which also had a crew on the scene. During the incident, KNTV camera operator Alan Waples was pistol-whipped. The man then threw Waples to the ground and hit him with the gun in the ear, causing a large gash and leaving a big bruise on his upper arm. The robber stole a camera and tripod belonging to KNTV and struggled to put it in a black BMW, before hitting Waples one more time and telling Sanchez to get onto the ground, she said. Off camera, the man pointed a gun at Crook, stole KTVU’s camera and tripod and fled, leaving behind an ammunition clip. Sgt. Michael Andraychak, a police spokesman, said the timing of the robbery and its location on a major pedestrian thoroughfare made the investigation a high priority. The attackers were described as three males, all wearing dark clothing, with one who had dreadlocks driving a late-model BMW with upgraded rims and no license plates, police said. The heists have prompted many stations to hire security guards to accompany crews, particularly for stories in Oakland. Many of the guards are former police officers. Crook was attacked in February and robbed of a live transmission unit and a microphone while reporting from a Hayward doughnut shop on a story about the lottery. Last August, Liu was hit in the head by a woman while working a story about the shooting death of a man by private security guards at an East Oakland swap meet.