A pair of US drone strikes against Pakistan’s South Waziristan Agency have killed at least 15 people, including members of the militant faction run by Maulvi Nazir. The militants were killed in the first attack, near the Afghan border.

The attacks are the first to target the Naziri faction since October, when several US strikes killed members of his family. Nazir’s faction has for the most part been on good terms with the Pakistani government, but has fought the US off and on, usually launching attacks in response to drone strikes.

Officials termed all the slain as “suspected militants” but so far there are no indications who the second attack, which targeted a car near North Waziristan, actually killed. This is common among US strikes, many of the victims of which are never publicly identified.

The strikes mark the ninth time US drones have attacked Pakistan since the beginning of the year, and is the deadliest such attack. Last week, US drones killed 13 people in South Waziristan.