New Delhi, Feb 4 (IANS): Expressing "deep sorrow" and "concern" over the death of a student from Arunachal Pradesh, President Pranab Mukherjee Tuesday asked all citizens to "work hard" to strengthen the "bonds of friendship and amity" amongst diverse communities.

In a statement, the president expressed deep sorrow and concern over the death of 19-year-old Nido Tania, son of an Arunachal Pradesh legislator, in Delhi last week.

Condemning the violence which preceded Tania's death, the president called upon law enforcement agencies to make every effort to bring the guilty to justice and ensure the safety and security of all who live in the capital city.

"New Delhi is home to people from all parts of the country and the core principle of unity in diversity must always be respected," the statement said.

Mukherjee called upon all citizens to "work hard to strengthen bonds of friendship and amity amongst the diverse communities that constitute our nation".

Tania was beaten up by shopkeepers in a south Delhi market following a quarrel over his appearance and clothing. He died in a hospital Jan 30. The victim's friends say it was a racial attack.