They all live in the Naza Vegas building in Watthana district, where fellow Iranian suspect Leila Rohani also lived.
Mr Mehrded, 33, was detained yesterday afternoon when police raided a room on the 14th floor of Naza Vegas.The police seized a computer, a mobile phone and some other objects from the rental apartment for inspection.Mr Mehrded did not respond to police officers who spoke to him in English, so he was detained for interrogation at a later time when police can appoint an Iranian interpreter.
Police tracked him from information found in the Sim cards of Saeid Moradi, 28, and Mohammad Khazaei, 42, the first two suspects detained in connection with the Feb 14 bombings.
Mr Moradi was badly injured in one blast and is being treated at Chulalongkorn Hospital, while Mr Khazaei, 42, was arrested at Suvarnabhumi airport later the same day as he tried to leave Thailand.
The call logs on the Sim cards showed Mr Mehrded had regularly communicated with the two suspects by mobile phone, police said.On Feb 14, he allegedly was waiting for the other suspects in front of the Israeli embassy on Asok Road, police said.
The man entered Thailand on July 27 last year and had overstayed his visa by almost five months.
His visa expired on Sept 29, 2011.Police investigations also showed he had lived at the apartment since his arrival and rarely went out or met people. He survived on food delivered to his room by an Iranian who worked as a chef at a hotel in Soi Nana, off Sukhumvit Road.Rahimi Rad Iraj, the chef, and Mahboobh Tasbehi, his wife, were apprehended late yesterday afternoon at room No. 21122 on the 11th floor of the same building, police said.
In another development, deputy police chief Pansiri Prapawat said police had obtained pictures of a number of people who posted stickers bearing the word "Sejeal" along a road in Klong Toey district.
Police believe the stickers are linked to the bomb suspects.Security camera footage showed the sticker-posters at work, Pol Gen Pansiri said.He said he could not go into detail regarding the suspected posters as police were still testing DNA samples collected from some of the Sejeal stickers.The origin of the stickers remains unknown, he said.