A group of men attacked Junaid Khan and his three brothers last month in an apparent row over seats as they travelled by train from New Delhi to their home in the neighbouring Haryana state, killing him and injuring one of his brothers.

One brother said the attackers accused them of carrying beef, a meat popular among many Indian Muslims, but shunned by most of the country's Hindus, who revere cows as sacred.

Haryana's deputy inspector Mohinder Singh said police acted on a tip-off and arrested the chief suspect, who officers believe stabbed Khan to death, in the Dhule district of western Maharashtra state late on Saturday.

Singh said they had now arrested six people in connection with the teen's death.

India has been reeling from a spate of vigilante murders in recent months, especially targeting Muslims for allegedly killing cows or eating beef.