A witness to the shooting of congresswoman Gabrielle Giffords described the acts of the two men who tackled the shooter as "heroic."

Alex Villec, a 19-year-old volunteer, organized the line of constituents when the shooter approached the line outside Safeway. Villec said he didn't see two men tackle the gunman, though he spoke with one of the men afterward. That tackler, he said, was next in line to greet Giffords.

"It's heroic," Villec said. "I'm at a loss for words to describe the courage it takes to do a thing like that."

Earlier, the shooter asked, "Can I talk to the congresswoman?" or something to that effect, Villec said. Villec said he told him to stand at the back of a line to wait for about 20 minutes. A few minutes later, the man left the back of the line and walked toward Giffords amid a group of 20 to 25 constituents, employees and volunteers.

"He was intent," Villec said. "He was intent when he came back - a pretty stone-cold glance and glare. … I didn't see his gun, but it was clear who he was going for. He was going for the congresswoman.

"A few staff members were caught in the crossfire. … His goal was the congresswoman."

The shooter walked past Villec, past tables and toward Giffords. Villec said he saw the shooter raise his hand and heard gunshots before ducking behind a pillar and later running across the Safeway parking lot to a bank for safety.

"It was bedlam," he said. "People were getting down on the ground. They were screaming. I just did what I could to keep myself protected."

The weapon "sounded like a handgun." He said he didn't hear the shooter speak while firing. Villec said he heard someone cry, "Get down."

Villec, who was still shocked about his close call, knew the gravity of what occurred early Saturday.

"It's clear that this is a contentious district. Passions run deep on these issues, so much so that somebody would be compelled to do something like this," he said. "However, the kind of bickering that happens on a day-to-day basis never reaches physical violence.

"This is unprecedented - and it's going to send shock waves throughout the country."

Villec worked on Giffords' 2008 campaign and interned twice in the past year for her, both in Tucson and in Washington, D.C. The Catalina Foothills High School graduate volunteered Saturday in part to see old friends. He was set to return to Georgetown University today.