FRESNO, Calif. (KFSN) --Fresno Police and the Fresno County Sheriff's Office have people working to weed out terrorist activity.
They work directly with the FBI, but both agencies say preventing an attack is difficult.
When it comes to the names of people suspected of terrorist activity in Fresno County.
Sheriff Margaret Mims says she is on a need to know basis.
The information usually trickles down from the FBI to one of her investigators who is on the Joint Terrorism Task Force.
"If it doesn't rise to the level of, everybody should know, we will probably not find out about it, generally," Mims said.
On Monday, she learned more about Omar Mateen, who was on an FBI watch list at one time and even investigated twice first 2013 and again the next year.
"They could find nothing to confirm that he was, in fact, connected to a terrorist group, however, as it turns out, that feeling that he had evidently grew and culminated in the attack this weekend," Mims said.
Mateen killed 49 people and wounded dozens of others on the opposite side of the country. The shooting was far from Fresno but Fresno Police Chief Jerry Dyer says it still hits close to home.
"I can guarantee you, after this incident, there will be a significant amount of calls initiated to our office to check for suspicious activity or suspicious persons," he said.
Like Fresno County Sheriff Mims, Dyer has an investigator working with the FBI as well as liaison officers who report suspicious activity in the city to the Feds.
"The FBI then takes that information, analyzes it and provides it back to us," Dyer said.
For Mims and Dyer, the investigators on the inside decide what information and names to pass on.
Normally, Mims says it depends on several things, like how credible the threat is and whether there is a warrant for an arrest.
"Are they just going to think it, are they going to say it or are they really going to act out and that's a difficult thing to evaluate," Mims said."