Rebel leaders agreed Friday to discuss a truce extension proposed by the leftist government, and one of the best-known rebel commanders turned himself in to accept government amnesty.

Manuel Espinoza, the presidential spokesman, said "some advances had been made" during the second day of the peace talks. The government proposed extending the talks beyond their scheduled end on Saturday.Felix Garcia Hernandez, known as Alfa Lima, told reporters Friday that before he asked for amnesty he commanded more than 400 Contras in the Chontales region and had been in the rebel forces since the civil war began six years ago.

He said he met with representatives of the Nicaraguan army several times during the truce and decided to return because of his family and because he felt Nicaraguans should stop killing each other. He turned himself in Wednesday, and the Sandinista government announced it Thursday night.

Alfa Lima abandoned the rebel force with six of his men and said Friday he hoped to encourage more of his former comrades to take advantage of the amnesty.

"I am going to try to convince my men to come in. There are many out there who do not know what they are doing or why they are fighting," said the soft-spoken Alfa Lima, still wearing his camouflage uniform.

Alfa Lima's former commander-in-chief, Enrique Bermudez, was in Managua for the peace talks and said upon hearing of his decision, "We regret it. He was a field commander with a long record. We consider him a war casualty."

Although they agreed to discuss extending the cease-fire, which is scheduled to end May 30, the rebels still insist on an agreement that includes a firm schedule of democratic reforms.

According to a source at the negotiating table, Defense Minister Gen. Humberto Ortega, head of the government delegation, told the session "it would be difficult to reach an agreement by Saturday noon, but we are not discarding the possibility of a miracle, like the miracle at Sapoa."

Sapoa, a town on the Costa Rican border, was where the March 23 peace agreement was signed by the Sandinista government and the U.S.-supported rebels.

Alfredo Cesar, who heads the Contra delegation, said there was a "25 percent chance of an agreement."