CHICAGO -- Eduardo Sanchez had just arrived at the auto-parts warehouse where he worked and was about to put his lunch away when he heard a familiar voice behind him, offering a choice:
"Do you want me to tie you up, or do you want to die?"
The voice belonged to Salvador Tapia, a co-worker who had been fired from the warehouse six months earlier.
"I said, 'Tie me up.' I didn't want to die," said Sanchez.
Before Sanchez managed to escape and alert police, Tapia had shot to death the six remaining men in the warehouse, including two of the owners, who were brothers. Tapia, 36, was killed in a gun battle with police.
In an interview conducted in Spanish on Thursday, a day after Tapia's rampage, Sanchez, a 48-year-old father of three, described a nightmare scene of bodies, blood and gunshots, and told of the guilt he felt at not being able to warn his co-workers at Windy City Core Supply.
Tapia confronted Sanchez shortly after 8 a.m. and used a piece of rope to tie him to a metal rail.
Tapia told him the son of one of the owners -- a man who often arrived first to open the warehouse -- was already dead.
"He said, 'You haven't done anything to me. I am going to kill all of them. I want to kill everybody,"' Sanchez said.
Tied to the railing, Sanchez was forced to listen as Tapia killed the men one by one as they arrived for work.
At one point, Tapia returned to within sight of Sanchez. Sanchez said Tapia shot himself three times, fell to the ground, then stood back up.
"He looked like the devil. He was completely covered in blood," Sanchez said. "I got even more scared. I started thinking that if he didn't let me go he was going to kill me, too."
Police said Thursday the medical examiner had not found conclusive evidence that Tapia shot himself. Tapia had between seven and nine gunshot wounds, and three 9mm bullets from officers' guns were recovered from his body, police spokesman Pat Camden said.
Sanchez said the rope binding him had enough slack that he was able to work free from the rail. He went down a ramp and into the basement. From there, he nervously climbed a flight of stairs and made his way into an office, where he found Howard Weiner, one of the owners, and his son, Daniel, dead on the floor.
Sanchez ran out onto the street, his hands still bound behind his back. He met a truck driver headed to the warehouse, then ran into Robert Bruggeman, the company's third owner -- who police said was late to work because of an expressway crash.
Together, they alerted police.
On Thursday, authorities were continuing to investigate how Tapia obtained the semiautomatic pistol he used in the rampage. Because he was a convicted felon, Tapia was prohibited from owning a gun. Police were seeking to interview a Chicago resident who registered the gun in 1983, Camden said.
Acting Police Superintendent Phil Cline said Tapia had been arrested 12 times. He was convicted in 1989 of unlawful use of a weapon. He also had repeated domestic violence arrests. In 1997, he threatened his girlfriend, sister and brother-in-law with a gun.
"I knew he was going to snap. He had anger. I don't know where it was coming from. He was angry at the world," said his former girlfriend, Julia Camacho. "I knew if it wasn't me it would be someone else."
Police also said that Tapia had made threatening calls to the owners of the warehouse, but that no police reports were filed.
In addition to Howard Weiner, 59, and his 30-year-old son, the victims included Howard Weiner's brother, Alan Weiner, 50. The other shooting victims were Calvin Ramsey, 44, Robert Taylor, 53, and Juan Valles, 34.
Sanchez that when he and Tapia worked together, he was cordial toward Tapia, who was always nervous and irritable at work, but they were not friends.
Sanchez said he feels lucky to be alive but troubled by guilt.
"I feel bad because I could not warn the others that he was there. I don't feel good," Sanchez said. "I wish I could have warned them that he was there waiting to kill them."