Two motorcyclists have died following separate overnight road traffic collisions.

A motorcyclist has been killed in a single vehicle road collision in Co. Westmeath.It happened at around 2.20 this morning in the Kilmartins Roundabout area of the Dublin Road in Athlone.

The man in his 20's was pronounced dead at the scene. The Kilmartins Roundabout is currently closed to traffic and forensic collision investigators have been called to the scene. Junction 10 on the N6 is also closed and there are diversions via Junction 9.Gardai say all road users travelling between Athlone and Moate should use the M6 as a section of the R446 is also closed.The investigating team are also appealing for witnesses or anyone who may have dashcam footage to come forward. Elsewhere,a man has died in a road traffic collision between a motorbike and a tractor in Co. Cork.It happened at Gooseberry Hill in Newmarket just after 8 o'clock last night. The motorcyclist, who was aged in his 40's, was pronounced dead at the scene.The road remains closed this morning while a forensic examination of the scene is carried out. Gardai are also looking for any witnesses to the collision or anyone who may have dashcam footage to come forward.