Finnish prison officials have faced an unusual spike in violent attacks recently, says the Prison Officers' Union.

Within the past six months, eight prison guards have been the targets of violent attacks, both inside and outside of prisons, the Lännen Media (LM) newspaper consortium reported on Thursday.

Prison Officers' Union chairAntti Santamäki said that the large number of incidents cannot be mere coincidence.

"Usually prison workers only very rarely face direct violence in prisons, and even more rarely in their civilian lives," he said.

Crime syndicate's revenge?

The National Bureau of Investigation (NBI) suspects that the United Brotherhood (UB) crime syndicate may be behind the assaults, and that they are a response to a major operation by authorities to shut the organisation down.

Last spring LM reported that prisoners linked to organised gangs have tried to organise contract killings of at least three prison officers in Finland within the past couple of years. All three attempts were thwarted by authorities.

According to LM, in August the Criminal Sanctions Agency (Rise) warned all of its staff of the threat of violence from gang-associated prisoners.

That followed three violent incidents aimed at guards within a few months. In September it said that the UBcommissioned assaults on Riihimäki prison guards last summer.

Within the past week it reported that Rise will try toseparate gang members from the general prison population.