A former Russian mercenary was arrested for allegedly sending death threats to his rivals in Thailand.

Milo Yanovich, 25, reportedly threatened his rivals with photos of his weapon arsenal, and messages that he would 'shoot them to death one by one and splash pig's blood on them'.

The shocked recipients of the unsolicited messages from the former 'dog of war' were handed to cops.

Immigration police acting on a tip-off from an anonymous informant obtained a Criminal Court search warrant and raided Milo's room in the Makkasan area of Bangkok on October 28.

Police Major General Phanthana Nuchanart, deputy commissioner of the Immigration Bureau, said in an October 29 press conference that the Russian man was found keeping ammunition and firearms without a permit.

He said: 'The suspect said that he was a former mercenary in Russia. He claimed that the ammunition were not his but belonged to a Thai friend whose name he could not remember.'

Authorities seized from the room a .380 pistol magazine containing two bullets, 50 .380 Bullet Master rounds, 42 9mm bullets, and 16 .45mm bullets in a box near his closet.

The Russian was detained for illegal possession of firearms. He was hauled to the Din Daeng Police Station to face legal action.

Thailand has become a popular destination for Russian tourists escaping military conscription in the war with Ukraine. The Thai government has been spellbound by the wealth of the former Soviet Union powerhouse and had used visa-free programmes to encourage the influx of Russian holidaymakers.