Two TDs have been released from custody after being arrested during an alleged attempt to search two planes believed to be used by the US military.
Mick Wallace and Clare Daly were detained after getting into the airside area of Shannon Airport where two aircraft were parked away from the main terminal.
The Garda press office confirmed a man and a woman were arrested by airport police at 12.20pm after a security fence had been breached and they were subsequently handed over to local gardai.
The pair, both independent TDs, were detained at Shannon Garda Station.
Just over an hour later they were released without charge at around 1:30pm, according to a Garda spokesman.
A file on the incident has been sent to the Director of Public Prosecutions.
Ed Horgan, an anti-war campaigner with the Peace and Neutrality Alliance and the Shannonwatch group, said he witnessed the two arrests.
"The aircraft were being guarded by the Irish army and Clare Daly and Mick Wallace were arrested by airport police quite close to the aircraft," Mr Horgan said.
It is understood the two TDs were attempting to inspect a US Hercules transport plane and a second plane which is believed to be a Boeing 737 converted for use by the US military.
The TDs have campaigned for US military planes landing and refuelling at Shannon Airport to be searched independently to verify that allowing military aircraft at Shannon does not interfere with Ireland's status as a neutral country.