Authorities say they are investigating specific suspects for Friday's bomb threats that prompted evacuations at three courthouses in downtown Youngstown on Friday.

Mahoning County Sheriff Jerry Greene confirmed to 21 News that suspects are being investigated in connection with the threats that resulted in searches at the county courthouse, Youngstown Municipal Court and U.S. District Court.  Greene said he is not yet releasing the suspect's names.

Agents from the Youngstown Police Department Bomb Squad and several other agencies have searched buildings on Market Street which were closed as a result of the threats.  

Shortly before 10 a.m., someone called into Austintown Police Dispatch stating that four "detonation devices" had been placed inside of 120 Market Street, the address of the Mahoning County Common Pleas Court. 

The suspect allegedly said that another explosive device had been placed ion the "courthouse across the street," but did not specify whether the referred to the U.S. District Courthouse or the Youngstown Municipal Court on Front Street. 

Just after 10 a.m. a second call, apparently from the same person, was called into Austintown Dispatch requesting a ransom of $100,000, claiming the devices would detonate shortly after the noon hour.

The Sheriff's Office, U.S. Marshals, and the Youngstown Police Department Bomb Squad were dispatched to the courthouses and began searching. 

Greene said that a bomb-sniffing dog was called in from Stark County to assist. 

Meanwhile, the U.S. Department of Homeland Security deployed one of their bomb-sniffing dogs to search the federal courthouse. 

Greene said officials searched the buildings several times but found no detonation devices and waited out the 12:01 p.m. detonation time. 

Shortly after 1:30 p.m. officials said the Youngstown Municipal Court Annex building on Front Street had also been cleared. 

According to Sheriff Greene, several detectives are working on the case and are being assisted by the Federal Bureau of Investigations and the ATF.