The Solomon Islands police commissioner is believed to be seeking legal advice today following moves by the government to sack him.
The Prime Minister, Manasseh Sogavare, is threatening to remove Mr Castles following the Immigration Minister, Peter Shanel's arrest over the Julian Moti affair.
Mr Castles said in a recent statement he had done nothing more than uphold the rule of law and fulfill his constitutional and statutory responsibilities.
He declined to discuss the move but a spokesman says the commissioner is distressed that the Prime Minister's office released a press statement on such a confidential matter.
The spokesman says Mr Castles received a letter from the Police Minister late last week indicating his services were no longer needed.