BROOKLYN - New York City is on high alert this evening after intelligence officials unearthed a terror threat coinciding with the 10th anniversary of Sept. 11.

Officials say the threat may involve car and truck bombs, prompting law enforcement officers to set up checkpoints at bridges, tunnels and subway stations. Mayor Michael Bloomberg said the threat has not been confirmed, but that it is very specific and seems to fall in line with the day's commemoration ceremonies. Many residents say they still feel safe despite the rumors, even though several U.S. marshals have been roaming the streets near the Brooklyn Bridge. Police officers will be out in record numbers this weekend, with most staying on duty an additional four hours.Counterterrorism officials investigate unconfirmed threatsFeds warn of small airplane terror threats