"The reports are clear that policemen were also part of the mob that chased the US national...The local police cannot investigate the matter. The case will have international ramifications as the person concerned is an American," NCP Goa spokesman Trojano D'Mello told PTI.
Caitanya Holt had died at Korgao village on January 12 after he fell down in a paddy field while running away from a group of chasing locals who mistook him for a thief.
The NCP alleged that the police were trying to hush up the matter and demanded that CBI should take over the case.
Alleging that the law and order machinery had collapsed in the state, D'Mello said: "We have to find out whether any politician instigated the mob...Was there any drug connection (to it) or it's a fallout of some earlier criminal history."
"You run after a man (Holt), chase him to death and then say he died after choking on mud. There are no words to condemn it," D'Mello said.