Pakistan bombed Taliban government targets in Afghanistan’s major cities on Thursday night, officials from both countries said on Friday, with Pakistan’s defense minister calling the conflict “open war”.

Security sources in Pakistan said the strikes involved air-to-ground missile attacks on Taliban military offices and posts in Kabul, Kandahar and Paktia as well as ground clashes in multiple sectors along the border between the Islamic nations.

The Taliban said it launched what it described as retaliatory attacks on Pakistani military installations.

Both sides reported heavy losses, issuing sharply differing figures that Reuters could not independently verify.

“Our cup of patience has overflowed. Now it is open war between us and you (Afghanistan),” Pakistani Defence Minister Khawaja Muhammad Asif said on Friday.