The Mountain Road was closed with immediate effect due to ‘current significant pressures on emergency services’.

Highway officials said the situation would be kept under review and the road would reopen ‘as soon as it is safe and appropriate to do so’.

It reopened around 4pm.

The Department of Infrastructure made the announcement on its Facebook page just before 11am today.

It said: ‘The A18 Mountain Road (Ramsey to Creg Ny Baa) will be closed with immediate effect.

‘This decision has been taken in the interests of public safety, ensuring emergency crews can respond effectively and without delay across the network.

‘All road users are reminded to ride and drive to the prevailing conditions and to do so responsibly at all times.

‘The situation will be kept under review and the road will reopen as soon as it is safe and appropriate to do so.’

Meanwhile, in their latest update, police said that since its last warning, eight people have been arrested for entering closed roads, including three on pushbikes.

A spokesperson said: ‘Do not enter closed roads at any time. Riding, driving or even walking onto a closed road places you and others at risk and you may be placed before the next available court.

‘It puts riders, spectators, marshals and yourself in danger, and it has wider impacts on the running of racing.

‘We will continue to work with marshals to prosecute individuals who enter closed roads, particularly where people are put at risk. Please do not ruin today’s racing by making unsafe choices.’