PHOENIX (AP) _ Three alleged gang members were arrested on charges of plotting to assassinate Arizona's prison chief, who investigators say was just moments away from being gunned down at a restaurant when two officers walked in for lunch and scared the hit men away.

Authorities said Tuesday that the former prison inmates were bent on killing Corrections Director Terry Stewart in retaliation for his get-tough policy toward gangs behind bars. The men were arrested this week.

An informant told police that hit men followed Stewart to a Mexican restaurant in Phoenix last July and were ``reaching inside their clothing for their weapons'' when the officers showed up, police spokesman Mike McCullough said. The hit men left without anyone realizing what was up.

``The Phoenix Police Department saved my life by those officers' happenstance arriving,'' Stewart said Tuesday.

McCullough said the informant told officers that gang members could also be plotting to kill deputy corrections directors.

Police said the plot was prompted by Stewart's policy of putting key gang members in solitary confinement and letting them out only one hour a day _ a crackdown that is said to have crippled gangs' ability to operate.

All three defendants are allegedly members of the New Mexican Mafia, a group that evolved from the Mexican Mafia that started in California prisons during the early 1970s. Members of the New Mexican Mafia are said to be younger and more violent than their predecessors.

The three former inmates, all of Phoenix, were arrested Sunday and Monday. Raymond O. Llamas, 32; Michael A. Garcia, 37; and John A. Alday, 27, were charged with conspiring to commit murder and other offenses.

McCullough would not specify what role the three men played in the plot. He said others may be involved.

Garcia and Alday were held on $1 million bail. Llamas was freed on $32,000 bail; he was the only one who had a lawyer present when he appeared in court.

``I'm outraged. It's absurd. It could have an impact on our case where we're now very concerned about the safety of our witnesses as well as Terry Stewart,'' prosecutor Rick Romley said of Llamas' release.

Llamas' attorney did not immediately return calls. The two other defendants did not yet have lawyers.

The alleged plot came to light in November when an inmate was stabbed by another inmate, supposedly for failing to carry out a killing ordered by the gang.

The victim sought police protection and told them about the plot against Stewart, McCullough said.

Stewart said the alleged attempt on his life proves the lockdown has frustrated gang members: ``If the policy, wasn't working they wouldn't be concerned about this.''