Around-the-clock security has been introduced at a tower block after a series of fires sparked arson investigations.

Police are now probing the cause of the blazes at Invicta House in Margate following a spate of suspicious incidents in the past week.

An arson investigation has been launched by detectives and the fire service after fires in a bin chute and bin stores sent smoke billowing up through the building.

It comes as fire safety improvements are due to take place at the tower block after a range of improvements were highlighted.

A police spokesman confirmed the investigation is taking place after the first fire on July 7 was followed by four more this week with the latest on Saturday.

The council-owned block of flats in Millmead Road is managed by under-fire firm East Kent Housing (EKH), which says it is stepping up security patrols around the clock and working with Thanet District Council, police and the fire service.

A spokesman for EKH and the council said: "We take fire safety extremely seriously, and having been made aware of the recent incidents at Invicta House we have been liaising closely with local police and Kent Fire and Rescue Service.

"We have increased our presence on site and are providing a 24 hour, seven day a week security presence for the block.

"We would again emphasise regular fire safety advice to all residents and visitors, and we are distributing leaflets with this advice on to all residents this week.

"We encourage people to be careful and aware of any dangers, and urge everyone to ensure they do not place lighted items in the bin chutes."

The fire service says it will continue to work with police to establish the cause.

Work is due to begin "imminently" to carry out fire safety enhancements, EKH and Thanet council confirmed.

The tender for a contract was issued earlier this year for works at Invicta House.

"This includes new front entrance and communal doors, stairwell fire protection enhancements, and upgrades to the fire alarm system and work will be starting imminently," a spokesman added.

"This work is part of a broader programme of fire safety enhancements that will be delivered in a series of phases by East Kent Housing and Thanet District Council."

Invicta House has been a high profile fire risk since a huge blaze needed 50 firefighters to tackle flames from the building in 2007.

Anyone with information about the latest fires can call Crimestoppers anonymously on 0800 555 111.

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