Basque separatists said Wednesday they were surprised by a weekend car bombing at Madrid's international airport and insisted a nine-month cease-fire is still alive despite the attack, which the government blamed on the Basque armed militant group ETA.

Also on Wednesday, rescuers found the body of one of two men missing in the rubble.

Ecuadorean immigrant Carlos Alonso Palate, 35, was believed to have been sleeping in a car in the multi-story parking lot targeted in the explosion at Madrid's international airport, a National Police official said.

Another Ecuadorean, Diego Armando Estacio, 19, who was at the airport separately and also sleeping in a parked car at the lot, remains missing under tons of concrete and metal rubble.

Saturday's attack prompted the government to suspend plans for peace talks with the separatists.

Pernando Barrena, a leader of Batasuna, ETA's outlawed political wing, stressed there is no proof ETA is responsible because it has not issued a statement claiming responsibility. "The political process has not been broken," he said.

Click here for FOXNews.com's Europe Center.

However, a caller who warned authorities before the explosion said he represented the group.

Another senior member of Batasuna, Joseba Alvarez, told Basque radio the bombing had taken the party by surprise — even though party officials recently said the peace process was in crisis.

"Nobody expected an attack like the one in Madrid," said Alvarez. He demanded that ETA explain the reason behind the attack, which left two people missing and 26 people injured.

Batasuna and ETA moderates who favored negotiations appear weakened after the bombing. Their comments on Wednesday also suggested a split between ETA and Batasuna, which could further complicate attempts to negotiate a solution to the Basque region's decades-long struggle for autonomy.

Batasuna is seeking recognition as a legal political party. During the cease-fire, it has asked that Basque separatists now in prisons around Spain be transferred to the Basque region of northwestern Spain.

In the aftermath of the bombing, the government suspended plans for peace talks with the separatists. On Tuesday, Interior Minister Alfredo Perez Rubalcaba went even further, saying that that the process was "broken, over, liquidated".

For a fourth consecutive day, crews used heavy machinery to remove tons of concrete and metal at the five-story airport parking garage where the bombing occurred. But they have given up hopes of finding two missing men alive.

Two Ecuadoreans are believed to have been sleeping inside separate parked cars when the blast occurred.

"The temperatures reached in the area are incompatible with life," said Alfonso del Alamo, director of Madrid's emergency services.

He said some 154 charred cars have been removed from the site, all unrecognizable as vehicles — although rescuers have not found the Ecuadoreans. More than 600 cars were in the garage at the time of the explosion, which caused a major fire.

"We still work with the hope of finding the bodies and that these can be recognized," Del Alamo said.

Madrid town hall has estimated that 40,000 tons of rubble will have to be removed from the bomb site at the airport's gleaming new Terminal 4.

If the two men are found dead and Saturday's bombings is definitively linked to ETA, it would be ETA's first fatal attack since May 2003.

ETA's campaign for an independent Basque state has killed more than 800 people since the 1960s.