New Delhi: The marble walls of one of the world’s majestic monuments, Taj Mahal, have started to turn green and black, reportedly due to insect attack.Also Read - No Entry Fee: Visit Taj Mahal, Agra Fort And Other Historic Sites Free Of Cost Today. Here's Why

An Archaeological Survey of India (ASI) official said that it has become a persistent issue since the bacteria from the filth floating in Yamuna nearby provides a healthy breeding ground for insects. Also Read - Delhi Jal Board Blames Haryana Govt For Dipping Levels of Yamuna River; Urges Urgent Release of Delhi’s Share of Water

According to the ASI, black and green patches have started to appear on the white walls and these patches are actually the excreta of the insects. This can potentially damage the marble surface and the designs on it. Also Read - Activists Take Royal Sand Bath In Waterless Yamuna On The Occasion Of Ganga Dussehra

Earlier, Taj Mahal used to suffer from bug attacks only during the months of April and October.

Cleaning and restoration work has now been undertaken by the ASI, whose appointed workers have undertaken the herculean task of scrubbing and washing off the green, black patches.

A senior official said that distilled water is being used for the process. A long-term solution for this could be to clean the Yamuna river, the official hinted.