THE death of Sheku Bayoh in police custody while being restrained by officers two years ago is one of the longest outstanding probes on the police watchdog's books.

The 31-year-old trainee gas engineer died allegedly as a result of positional asphyxiation caused by what is claimed to be heavy-handed methods of up to six police officers who arrested him in Kirkcaldy in May 2015.

The family Aamer Anwar has always said he wanted to know why officers needed to use batons, CS spray, leg restraints and handcuffs to subdue him.

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The family of the Sierra Leonean man set up a campaign for answers amid fears race may have played a part in his death, and met the previous Lord Advocate, Frank Mulholland QC to discuss their concerns.

The Police Investigations and Review Commissioner (PIRC) provided a full report on the death of Sheku Bayoh to the Lord Advocate, James Wolffe QC in August last year.

PIRC submitted an initial report in August 2015, but had to make an extra submission relating to "additional lines of investigation" which came up during their inquiry.

But it later emerged that further investigation is required before a decision can be reached on whether criminal charges should be brought against any officers or the force.

Whatever the result, Mr Bayoh's family are said to be suing.