OAKLAND, Calif. -- Oakland police say they're closing in on some of the men responsible for the recent takeover style robberies plaguing the city’s restaurants.

The city's assistant police chief says investigators have a good idea who they're looking for, but they're still asking for the public's help because they need a little bit more information and evidence to make the charges stick.

"We have some people we've identified. We don't have enough to arrest all of them," says Assistant Police Chief Howard Jordan.

There have been at least nine takeover robberies in Oakland, Berkeley and Emeryville in recent weeks. Investigators are examining evidence for similarities and trying to see if one group is responsible for all the crimes.

Two sources told KTVU News that police are preparing to announce the “good news” that suspects are in custody. But Assistant Chief Jordan says a press conference scheduled for Tuesday has been canceled.

"We're still trying to gather evidence and photo lineups; ask people to look at pictures," explained Assistant Chief Jordan.

While police are trying to solve the takeover style robberies, Oakland merchants are nervous. Ed's liquor store has been a fixture in East Oakland for 11 years. On Saturday night, an armed gunman walked in and tried to hold up the store.

Owner David Pulido says his brother Pedro shot the gunman three times, critically injuring the man.

Pulido says he is prepared to defend himself; he packs a pistol in his waistband and wears a bullet-proof vest.

"Somebody try to kill me and they take the chance, I'm gonna shoot him back. That's my life. I got a family to support," said Pulido

This is the second time within days that a business has fought back. On Thursday night, a corner store clerk in East Oakland also shot and injured an armed robber.

Oakland police say they do not believe the corner store robberies are committed by those responsible for the takeover-style robberies that have primarily targeted restaurants.