A threat to blow up vehicles full of explosives prompted closure of two major Baltimore highway tunnels for about two hours on Tuesday, in the latest incident to unnerve the U.S. public and force officials to defend their actions as necessary precaution.
The closure of the Baltimore Harbor Tunnel and the Fort McHenry Tunnel, clogging traffic on a major East Coast thoroughfare, was based on information from an "ongoing investigation" by the FBI, state and local authorities, Maryland Transportation Authority Police Chief Gary McLhinney said.
Searches of the tunnels and various vehicles turned up nothing suspicious, McLhinney said in announcing the resumption of traffic along the heavily traveled north-south Interstate 95 highway reports Reuters.
Authorities questioned the credibility of the threat but looked for several men who the source said would drive explosives-laden vehicles into the tunnel, said another federal law enforcement official, who also spoke on condition of anonymity.
"While the information was somewhat specific, to date the intelligence community has not found evidence that corroborates the information," FBI agent Richard Kolko said.
Shortly before the tunnels were reopened, authorities made about a half-dozen raids in the Baltimore area, said city Police Commissioner Leonard Hamm.
Four people were arrested on immigration charges at businesses with Middle Eastern connections, said a federal law enforcement official, who spoke on condition of anonymity.
One of them was arrested as a result of information supplied by the FBI's Joint Terrorism Task Force, which was heading the tunnel investigation, the source said. That arrest, made at a pizza shop, may be connected to the threat, the source said.
State and local authorities closed the tunnels "out of an abundance of caution," said Jim Pettit, a spokesman for Gov. Robert Ehrlich's homeland security office, informs the AP.
Russian officials have repeatedly declared that Israeli aviation poses a threat to the Russian military in Syria.