CPI(M) general secretary Sitaram Yechury asked the Centre to prohibit cow protection committees and urged the state government to ensure action against the those guilty as per law.
"We strongly condemn the incident. It will communalise the situation and aggravate the Kashmir problem further," he said over phone from Siliguri in West Bengal.
Yechury said members of the tribe were attacked when they were taking their cattle herd to Kashmir Valley, a practice, he said, followed every year by them during summer to feed the animals.
Two members of a nomadic family were beaten up by a group of people who mistook them for cow smugglers in Jammu and Kashmir's Reasi district on Thursday, the police said.
Bovine smuggling within regions and districts in the Jammu division is banned by the state government.
However, these members had the requisite permission for transporting animals on foot, police officials added.