(NewsNation) — There are a range of criminal and national security threats that have only grown throughout the years, FBI Director Chris Wray said, making demands on the FBI higher than they’ve ever been.

Last year, 73 law enforcement officers were killed on the job — more than any year since the 9/11 attacks, Wray said.

“This June, more officers were murdered in this country than in any single month in the past four years,” Wray told the Senate Judiciary Committee on Thursday.

The number one concern Wray said he hears from police chiefs across the country is rising violence.

“Whether it’s gangs terrorizing a neighborhood, well-known trigger-pullers who keep finding their way back out onto the streets, robbery crews graduating from carjacking to aggravated assaults and worse — the violent crime problem is real, and it’s one we are determined to combat,” Wray said.

In Arizona, more than a dozen people were arrested on drug and firearms charges as part of a gang investigation, while in California, eight were arrested and pounds of amphetamine, fentanyl and multiple handguns were seized. Meanwhile, 18 suspected drug traffickers with cartel ties were arrested in Texas.

“That is just three FBI field offices in a single week,” Wray said.

John Cornyn, (R-Texas), asked if the criminal street gangs are the key to distributing the illegal drugs coming in, and the violence that has been seen in areas along the border.

In response, Wray said “criminal street gangs” are the vehicle that they interact with the most as a distribution mechanism for drugs that are coming from the cartels and transnational criminal organizations south of the border.

To combat a number of “serious security issues” at the border, Wray said the FBI is constantly sharing watch listing information with the Department of Homeland Security, and the agency’s partners.