LOS ANGELES (Reuters) - A California police officer responding to a report of a man with a gun shot to death an unarmed 73-year-old man who approached the officer without taking his hands out of his pockets, police said on Tuesday.

The family of victim Francisco Serna has called the shooting unjustified and told local media he had at least some form of dementia.

The shooting early on Monday in Bakersfield, about 100 miles (161 km) north of Los Angeles, follows an intense debate and several protests in the United States against police use of force on minorities and the mentally ill.

The Los Angeles Times and other local media have reported that Serna was carrying a crucifix.

At a news conference on Tuesday, Bakersfield assistant police chief Lyle Martin did not discuss what Serna was carrying but said he was unarmed.

Serna was acting strangely as he approached a woman in the driveway of her house while she was being dropped off by a friend in a car just after midnight on Monday, Martin said.

He kept his hand in his jacket pocket and the woman believed he had a gun so she ran into her house, Martin said.

Her boyfriend or husband later called emergency dispatchers to report a man with a gun was outside, Martin said.

When police officers arrived and spoke with the woman outside her home, she pointed out Serna as he exited his own property across the street, Martin said.

She told the officers he was the one who had approached her. Serna was walking toward the officers with his hands in his jacket pocket, Martin said.

The officers, fearing he had a gun, took cover and told Serna to stop and take his hands out of his pockets but he did not obey, Martin said.

One officer opened fire seven times on Serna, shooting him to death within 20 to 30 seconds of the woman pointing him out, Martin said.

“This is a very tragic event,” Martin, who takes over as police chief in Bakersfield this week, told reporters at the news conference.

The officer who opened fire, Reagan Selman, has been on the Bakersfield police force since July 2015, Martin said. He has been placed on leave as the shooting is under investigation.

A spokesman for Bakersfield police could not be reached for further details on the shooting.