HONOLULU -- For the first time since the escape of four inmates from Waiawa Correctional Facility, the state's Department of Public Safety on Tuesday discussed the investigation.

Prisons officials said it looks like the inmates -- Elijah Keakahumoku, Jordan White, George Thomas and David Carvalho -- planned the escape for two weeks prior to the breakout. Authorities had rounded up the four escapees by early Tuesday morning. Read more about the inmates' capture.

Waiawa Correctional Facility is a minimum security prison that has no alarm system, according to public safety officials.

Honolulu police said the four inmates just walked away from the facility -- sometime between 11 p.m. Saturday and 1:10 a.m. Sunday.

"Our systems are in place. Our systems are good," Public Safety Deputy Director Joe Booker said. "One thing that we can do is sort of update our accountability process. Maybe be more accountable, more supervision at the institution."

Booker said a preliminary investigation found, "This was planned. The inmates worked on this a couple weeks ago."

The four men were in the same housing unit at Waiawa.

Correctional officers said they saw the men in their beds two hours before they discovered them missing at 1:10 a.m.

Prisons officials alerted police, sheriffs and others involved in the search for the escapees. It was not until noon, 12 hours after the escapes, that the public safety department released the inmates' names and pictures to the media and public.

"As you know, Waiawa sits in a very rainy area. We had some problems with our cabling and some of the faxing, some of the wiring because of the rain in Waiawa," Booker said.

Booker said the men face second-degree escape charges. If convicted, they face up to five years in prison.