VRINDAVAN, India (AFP) - Revellers have begun painting the town red across India at the start of riotous celebrations to mark the spring festival of Holi, including in a town usually associated with grief as a so-called "city of widows".

Holi, also known as the festival of colours, is celebrated across India this week as revellers flowerbomb each other with powdered paint, with festivities reaching a crescendo on Friday, which is a public holiday.

But some of the most moving celebrations have been in Vrindavan in the northern state of Uttar Pradesh, home to around 2,000 widows who have been shunned by their families after the deaths of their husbands.

While the idea of widows taking part in any kind of celebration has been traditionally frowned upon, the widows of Vrindavan have been joined by hundreds of other women since they began marking Holi three years ago.

"The best part about the festival is that we get to change and wear different clothes than those that we wear almost everyday," Ms Manu Ghosh told AFP after taking part in a Vrindavan paint fight on Tuesday.

"We can dance, sing and mess around together. The food, particularly the sweets during Holi, also remind me of the days when my husband was still alive," said the 85-year-old, who was widowed 21 years ago.

There were similarly joyous scenes in the city of Mumbai on Wednesday, where disabled youngsters sprayed and smeared each other with a rainbow of colours.