THE police chief whose officers arrested a black academic at his home said his department was "deeply pained" by President Barack Obama's statement that they acted stupidly.

In his first statement since the arrest, Commissioner Robert Haas of Cambridge police praised the arresting officer, Sgt James Crowley and said his actions were in no way motivated by racism.

Sgt Crowley, who is white, has been criticised for arresting Harvard professor Henry Louis Gates in Cambridge, a suburb of Boston, Massachusetts. Professor Gates has accused the police of racial profiling.

Police say Professor Gates flew into a rage when officers asked him for identification while investigating a report of a break-in at his home near the university.

At a White House press conference, President Obama said officers "acted stupidly" in arresting Professor Gates.