At least 72 people including children, women were killed and around 300 injured after a suicide bomber blew himself up at parking area in the Gulshan-e-Iqbal Park on Sunday.
#PrayForLahore became one of the top trending topics on Monday. #IndiawithPakistan was also used by some users.
The park was overcrowded as Christians were celebrating Easter with funfair in the premises when the blast took place.
Bollywood actors like Sonakshi Sinha, Siddharth Malhotra expressed their grief over the terror attack in Lahore.
Prime Minister Narendra Modi spoke to his Pakistani counterpart Nawaz Sharif and offered his "deep condolences" to the victims of the terror attack in Lahore park that left at least 72 dead, mostly women and children.
The responsibility of the brutal attack by a suicide bomber was claimed by Jamaatul Ahrar, a splinter group of the Tehreek-i-Taliban Pakistan (TTP).