LOS ANGELES — The sheriff of a US city where a gunman killed four people including three military personnel in a restaurant compared the shootings to the 9/11 attacks Wednesday.

The comments came as authorities named the victims of Tuesday's attack in Nevada state capital Carson City, in which a lone gunman opened fire on military personnel and others in a pancake restaurant.

While downplaying any link with the anniversary of 9/11 this week, officials said that they had ordered personnel from a nearby National Guards center from wearing uniform outside the base.

"People suffered yesterday, in very much the same way as we suffered on that day, on 9/11," said Sheriff Ken Furlong, giving an update on the shooting by a local man, identified as Eduardo Sencion, 32, who had mental health problems.

He added: "People came to work, people stopped by their restaurants, people got up and started their daily routines not expecting to be disrupted as we were yesterday."

"Yesterday in Carson City was not unlike 9/11," he said. "Families, businesses, entire communities and an entire nation have been affected by what happened here."

Sencion turned the gun on himself after his shooting rampage in the International House of Pancakes, a chain restaurant, early Tuesday. In all he shot 11 people with an AK-47-style assault rifle, four of whom died.

Although investigators have not yet determined a motive for the shootings, five of those targeted were National Guards members, wearing uniform in the restaurant only a few miles from their base.

Military officials said Wednesday that security at base had already been increased ahead of Sunday's 9/11 anniversary, and that staff had been ordered not to wear uniform off base hours after the shooting.

Furlong said the Nevada city would recover.

"We're a resilient society... Just as we were and are planning on doing this weekend a memorial for the 9/11 events," he said.

"In many cases such as we're doing with 9/11, we memorialize those that have been lost as a result of horrendous acts like this," Furlong said.

"I hope that we never forget. I think it would just be a sin if we were to forget," he said