India, March 17 -- Afghanistan on Monday accused Pakistan of carrying out an airstrike on a drug rehabilitation hospital in Kabul that it said killed at least 400 people, sharply escalating a conflict between the neighbours that has intensified over the past three weeks.

The strike came hours after Afghan officials said the two sides exchanged fire along their shared border, killing four people in Afghanistan, as the deadliest fighting between the neighbours in years entered its third week, according to the Associated Press.

Pakistan on Tuesday rejected Afghanistan's allegation that its airstrikes hit a hospital in Kabul, calling the claim "false and misleading," according to Pakistan's information ministry, Reuters reported. It had ear...