By Brendan O'Brien
(Reuters) - Los Angeles-area investigators have found no connection between the victims of a mass shooting at a Monterey Park, California, dance hall and the elderly man who carried out the massacre last weekend, authorities said.
The 72-year-old assailant, Huu Can Tran, on Saturday killed 11 people and wounded nine others at the Star Ballroom Dance Studio, a venue just east of Los Angeles that is popular with older patrons of Asian descent. The attack took place during the two-day Lunar New Year celebration, one of the most festive events on the calendar for many Asians.
"Based on interviews the investigators are still conducting, they have not been able to establish a connection between the suspect and any of the victims," Los Angeles County Sheriff Robert Luna said during a news conference late on Wednesday.
The Monterey Park rampage was the first in back-to-back mass shootings in California in the past few days. On Monday, a gunman killed seven people at two mushroom farms in the coastal Northern California city of Half Moon Bay.
Investigators have been unable to tie Tran romantically to any of the victims and have determined that he had not frequented the dance studio in the last five years, despite earlier reports that he was a regular at the establishment, Luna said.
In addition to conducting numerous interviews, investigators have searched Tran's home in Hemet, about 80 miles (130 km) east of Los Angeles. They have yet to identify a motive, he added.
"It's frustrating when something like this happens that is so tragic. We are trying to understand it, and it doesn't make sense," Luna said.
Investigators did find a motorcycle registered to the suspect parked one block from the dance hall. It was parked there just before the shooting as an alternative getaway vehicle, Luna said.
After carrying out the shooting at the dance hall, Tran drove a short time later to a second dance hall in Alhambra, where that club's operator disarmed him before he could open fire.
The next day, Tran shot himself to death behind the wheel of his vehicle as police closed in on him south of Los Angeles.
Tran used a MAC-10, a semi-automatic gun, in the shooting. He purchased that gun in 1999 but it was not registered with the state of California, Luna said. Police recovered two other weapons, the pistol Tran used to take his own life and a rifle at his home.
Near San Francisco, Chunli Zhao, a 66-year-old immigrant farm worker, was formally charged with premeditated murder on Wednesday in the shooting at Half Moon Bay. The Chinese citizen faces seven counts of murder and a single count of attempted murder, and could be sentenced to death if convicted.
(Reporting by Brendan O'Brien in Chicago; editing by Jonathan Oatis)