'Dangerous times': 4 federal agents shot this week

It has been a particularly perilous week for federal law enforcement.

On Monday, DEA Special Agent Michael Garbo, a 16-year veteran of the agency, was shot and killed during an operation in Tucson, Arizona.

What started as a routine investigation with DEA agents following up on tips that illegal drugs were being transported on an Amtrak train from California turned deadly as agents closed in on a suspected drug dealer.

The Tucson incident was one of three shootings in the past week that left at least 4 agents killed or wounded. As of Oct. 5, 55 law enforcement officers had been killed or wounded so far this year, approaching the five-year high set in 2018.

Another agent was also shot but not killed in the operation.

On Tuesday an ATF agent was shot and critically wounded in Nashville after a suspect opened fire team of agents looking to arrest him as he sat in his parked in his car outside a diner.

The dramatic scene was captured on security camera video. According to court records, the suspect, who died in the incident, was the target of a drug investigation.

Earlier this week, an FBI agent was shot and critically wounded while serving an arrest warrant with the U.S. Marshals in Racine, Wisconsin, according to police. They did not specify what the agent was doing other than categorizing it as “law enforcement activity.”

FBI Agents Association President Brian O’Hare said the association stands with those law enforcement agents who were shot at.

“The FBI Agents Association stands with these courageous agents, and our thoughts and prayers are with them and with their families,” O’Hare said in a statement to ABC News. “The FBIAA hopes that all Americans will join us in condemning these abhorrent acts of violence.”

And last Friday in Louisiana, a deputy U.S. marshal died after he was in a car accident while on duty.

Law enforcement leaders say these incidents show just how dangerous the profession can be.

“These tragedies are yet another painful reminder of what everyone in this audience knows firsthand: violent crime — particularly gun violence — has reached epidemic levels,” Deputy Attorney General Lisa Monaco told the Major City Chiefs Association during its annual conference on Wednesday.

Acting Deputy Director of the ATF Tom Chittum told ABC News in an interview it has been a hard week for federal law enforcement.

“This has been an incredibly difficult week for federal law enforcement,” he said. “Our hearts and thoughts and prayers go out to the families, the friends and to those officers that have been subjected to this gun violence.”

He said law enforcement is a dangerous profession, investigating the most serious violent offenders, but as of late it’s been more dangerous.

“I think they represent in a lot of cases, a callous disregard for life, no respect for them law,” Chittum said. “We have seen an increase in assaults on law enforcement officers that goes hand-in-hand with just the increase in violent crime we've seen across the country. It's a dangerous time out there and increasingly we see more rounds being fired, often in the ambush style attacks.”