Explosions and gunfire have been heard at the Indian consulate in the northern Afghan city of Mazar-e-Sharif.
Officials said the attackers had tried to enter the compound but had not been able to and were now in an adjacent building. Security forces reportedly cordoned off the area.
Indian diplomatic missions have come under attack from militants in the past in Afghanistan.
In 2008 and 2009, the embassy in Kabul was attacked twice, with dozens killed.
An Indian consulate official told the AFP agency from inside the compound that fighting was going on around the building.
No group said it was behind the attack. Indian officials said no staff had been harmed in the attack.
In May 2014, heavily-armed gunmen attacked the Indian consulate in Herat, while in August 2013 nine civilians died when the Indian consulate in Jalalabad was targeted.