Police arrested five Bangladeshis and detained three Indian teachers at an Islamic school for suspected involvement with yesterday's attack on policemen guarding the US cultural centre in Calcutta.
The arrests were made in Basirhat, 40 miles north of Calcutta and close to the India-Bangladesh border, last night, according to Mr Sourin Roy, chief secretary of the West Bengal state government. Those arrested are expected in court today.
Four Indian policeman were killed and 20 were wounded when they were attacked by armed assailants who fired from automatic weapons as they drove by the American Centre on motorcycles. One of the contract guards on duty at the centre was hurt.
Police said the eight arrested may have links to Pakistan's Inter-Services Intelligence spy agency.
Pakistan has denied its government is involved.
Meanwhile, the US cultural centre reopened today but the bloodshed and new heavily armed police commandos in front of the building were expected to dissuade visitors.
Indian officials have blamed the attack on Pakistan-based Islamic militant groups seeking to merge the Indian-controlled portion of the Himalayan region of Kashmir into Pakistan.
Other Indian officials said claims of responsibility were telephoned to police from Dubai, and suggested a connection with a criminal gang.
Pakistan-based militant groups have denied any hand in yesterday’s attack.
US State Department officials have not supported India's view on the attack.