Johor police have arrested a Kuala Lumpur resident, 26, for a Facebook posting allegedly critical of state monarch Sultan Ibrahim Iskandar.

Johor PKR chief Hassan Karim (picture above, seated middle) told Malaysiakini the suspect was arrested at the state police headquarters in Johor Baru at about 4pm today.

"He (the suspect) came to surrender himself at the station and requested that I accompanied him," said Hassan who is acting as his lawyer.