By David Raleigh
Update 8.45pm: An army bomb disposal have made safe an explosive device found underneath Thomond Bridge, in Limerick, earlier today.
The device is believed to be a First World War grenade, sources said.
It was retrieved from the River Shannon by a member of a Defence Forces Explosive Ordnance (EOD) unit at low tide, around 8pm.
Two EOD personnel were escorted by members of Limerick Marine Search and Rescue Service (LMSRS) on board their boat, flanked by another member on one of their jet skis, to the location where the grenade was earlier discovered underneath one of the bridge's archways.
The grenade was then transported from the scene by the EOD team to a secret location where a controlled explosion was to be carried out.
LMSRS Coxsain Officer, Karen Keehan said: "It was a successful job. We met the army bomb disposal team at 7.30pm and brought two of them to the grenade's location. They believe it's World War I era. It's a hand grenade."
"Everything was still intact. When the tide subsided they wee able to get it quiet easily before securing it in the boat."
"We then brought it back to our floating pontoon at Poor Man's Kilkee and the army unit brought it from there, by Garda escort, to detonate it."
A number of old cannon balls were also discovered at the bridge in recent days, where maintenance works to reinforce the bridge's structure are continuing.
Thomond Bridge has reopened to traffic and pedestrians.
Update - 5.16pm: AA Roadwatch are reporting that Thomond Bridge will remain closed until 7am Thursday.
Defence Forces personnel have been joined by divers attached to Limerick Marine Search and Rescue Service to survey the area where the device was found earlier today.
Earlier: Thomond Bridge in Limerick has been closed after a suspicious device, believed to be an old grenade, was discovered in the River Shannon underneath the bridge this lunchtime.
The object was found by a worker who was surveying archways underneath the 181-year-old bridge as part of ongoing maintenance bridge works.
The seven-arch rock-faced limestone road bridge, which spans the River Shannon was built in 1836.
A worker carrying out maintenance works on the bridge saw the object in the water around 1pm during low tide, and picked it up before realising it may pose a danger, sources at the scene said.
Gardaí were immediately alerted and have closed the bridge, with diversions in place.
Superintendent Derek Smart, Henry Street, said an Explosive Ordnance Disposal unit attached to the Defence Forces, based in Cork, have been contacted, and are currently traveling to the scene "as a precaution".
"One of the workers was at the foot of the bridge when they came upon a suspicious object. We are not sure what it is as yet but it looks like it may be an old grenade," he said.
"It's badly rusted," he added.
An eye witness, who was at the bridge at the time the object was discovered, said: "The worker was standing under an archway and they picked it up out of the water thinking it was a rock."
"There was a load of commotion then, when they realised it might be something dangerous. They contacted the gardaí and there was (workers) running up and down the bridge in a panic."
"The gardaí arrived and closed the bridge so they're waiting for the Army to come now," they added.