AYODHYA, India (AP) — The Indian city of Ayodhya on Saturday set a Guinness world record by illuminating hundreds of thousands of earthen lamps as part of an annual Hindu festival.

Representatives from the Guinness World Records handed over the certificate to Yogi Adityanath, chief minister of the northern state of Uttar Pradesh, after witnessing the lighting of 409,000 oil lamps on the banks of river Sarayu.

They monitored the effort with the aid of drone cameras

“Over 6,000 volunteers, majority of them college students, laboriously worked to ensure that lamps burn in a systematic pattern for the prescribed time frame,” Anuj Jha, district magistrate of Ayodhya, told The Associated Press.

Last year Ayodhya had set a record by lighting 300,150 oil lamps.

Hindus believe that their main deity Lord Ram was born in Ayodhya, where he returned after 14 years in exile. To celebrate his return, people light earthen lamps.

Hindus and Muslims are fighting a legal battle over the ownership of a piece of land in Ayodhya. Hindus believe that a temple existed on that place which was demolished by the Mughal Empire in the 15th century and a mosque was constructed. 

The mosque was demolished in 1992.

While Diwali is seen as a celebration of light, it has also been a cause for concern in recent years, as air pollution from lamps and fireworks lit as part of the celebrations exacerbates poor air quality in major cities.