OAKLAND -- Though questions remain about what led to a double homicide inside a Grand Lake district restaurant Monday night, prosecutors are preparing to charge a 21-year-old Oakland man in the killings, a spokesperson for the Alameda County District Attorney's Office said Wednesday afternoon.

Jamaine Gurley was arrested at his West Oakland home less than eight hours after two Wingstop employees, who were closing down the eatery shortly before midnight Monday, were shot and killed inside the business on Lake Park Avenue, across from Lake Merritt.

Gurley was booked into Santa Rita Jail in Dublin early Wednesday morning and is being held without bail. He is due in court in Oakland for an arraignment on Friday afternoon.

At a meeting with Grand Lake residents and merchants early Wednesday, Oakland police Area 2 Capt. Anthony Toribio told the group that two men went into the restaurant to get some food and there was an "encounter" with someone. He did not elaborate.

Gurley and the other man -- whose name has not been released -- ran to the back of the eatery, where they entered a refrigerated area, possibly to hide, authorities said.

When the two Wingstop employees -- later identified as Jose Santa Maria, 26, and Kenneth Bradley, 22, both of Richmond, went to investigate, they were both shot to death, Toribio said. Police said the men left the restaurant on foot.

An official at the Alameda County District Attorney's Office said prosecutors were reviewing the case against Gurley before finalizing charges on Friday.

A second man, who was identified using surveillance video from the scene, is being sought, but police have not said he is a suspect.

Police are still investigating, but believe the incident was not an attempted robbery or premeditated, Toribio said.

Still, police have already increased bicycle and foot patrols and next week the patrols will be bumped from two to three days a week, Toribio said.

"We want to saturate these areas and be visible to the community, as well as a deterrent to those that want to come in here and engage in criminal acts," Toribio said.

Additionally, Toribio said that undercover officers are being used more in the area as well as additional robbery and burglary enforcement units. A crime response team, a group of officers who can be directed to high crime areas are expected to be in place in that area in late August.

"I guess you hear about (killings) in East Oakland and West Oakland and you don't expect to hear it here, but obviously we're as vulnerable as they are," said longtime resident Dick Moore. "I'm very optimistic with the response team that this is going to change."

Jen Louise Dunning and Laura Johnson are both managers at Boot and Shoe Service on Grand Avenue, and are no strangers to crime in the area. Dunning said 50 percent of their employees have had their cars broken into or have been mugged. "There's obviously a problem and it seems to me that the sheer number of police officers in the city are not sufficient," Johnson said.

Contact Kristin J. Bender at kbender@bayareanewsgroup.com. Follow her at Twitter.com/kjbender. Contact Brittny Mejia at bmejia@bayareanewsgroup.com. Follow her at Twitter.com/brittnyariel.