At least 13 Iraqi soldiers died when armed men opened fire at a checkpoint they were manning in the northern city of Mosul, Qassim Abdullah, an army major, has said.
"A large group of terrorists drove up in five cars and opened fire on the Al-Hadhar checkpoint, before making off," Abdullah said on Monday.
Hadhar is a remote town on a major road south of Mosul, 300km north of Baghdad, in an area where Iraqi security forces often clash with fighters.
Targeting of academics
In a separate incident, two university academics were killed in the city of Mosul.
Armed men ambushed Talal Yunis, dean of the political sciences faculty of Mosul University, and killed him near the campus in the Shurat neighbourhood, said police Major Mohammed Ahmed.
Attackers also murdered Jaafar Hassan Sadeq, a professor of art history in front of his house in the Kafaat neighbourhood, police said.
Academics have become a target of choice for extremists opposed to liberal teaching in Iraq, and many hundreds have been killed or fled the country in the chaos since the US-led invasion of March 2003.