Crash barriers have been stolen from the TT course in Douglas and the west of the island.
The Department of Infrastructure said any further cases of safety equipment being taken would be reported to police.
It added replacing such roadside equipment costs the taxpayer significant amounts.
The DOI is currently preparing TT course for racing, including putting up signs and installing items for marshals.
Set your alarms! Young Farmers Concert tickets on sale this weekend
Tickets to one of the Isle of Man's most-anticipated theatre events will go on sale this weekend.
Treasury Minister says a tax threshold rise could cost £2.5m
Treasury Minister Chris Thomas says more work would be done to calculate how much raising income tax allowances would cost the government.
Snow shuts the Mountain Road
The Mountain Road has been closed today due to heavy snow and dangerous driving conditions.
Stop putting knives in recycling, says council
Douglas Council is asking people not to put knives in recycling boxes.
Bee Gees to release limited-edition box set
The Bee Gees are to release a special collector's set of their biggest hits this month - including previously unreleased material.
Northern Irish politician criticises Manx visa rules
Changes to Manx visa rules for fishing boats have caused a political row in Northern Ireland.
Elective surgical unit opens at hospital
Manx Care says its new Elective Surgical Unit is now open.
Piling rig on TT course tonight
A huge rig used to help build Peel's new sewage plant will be travelling along the TT course this evening.
