Kabul, Afghanistan (CNN) -- A spokesman for President Hamid Karzai expressed dismay Monday over four airstrikes in recent days by international forces in which dozens of civilian casualties have been reported.
"That's unacceptable to the Afghan government," said the spokesman, Aimal Faizi.
He said that Karzai had spoken with local officials and the families of the victims and then summoned International Security Assistance Force commander, Gen. John Allen, and U.S. Ambassador Ryan Crocker to the palace for an explanation.
Recently signed agreements between the United States and Afghanistan had been intended to stop such unilateral operations, said the spokesman.
"The reason for the MoUs and SPA was to Afghanize each and every thing in military operations and to put an end to unilateral operations," said Faizi, referring to two recently signed documents, a memoranda of understanding and a strategic partnership agreement over special operations.
"We do not have joint airstrikes," Faizi said. "It is unilateral when it comes to an airstrike."
He added that Allen had promised to investigate the issue and report back to the president. "General Allen said that his teams are investigating this incident and he regrets any loss."
A news release from the palace said: "During these bombings by coalition forces, which started since this Sunday in the Logar, Kapisa, Helmand, and Badghis provinces of Afghanistan, dozens of Afghan civilians -- including women and children -- were killed or wounded."
Karzai told Allen and Crocker that civilian casualties and the bombing of Afghan villages are unacceptable, the news release said. "President Karzai said that unilateral operations by NATO forces and bombing civilians is not only an issue of Afghan sovereignty, but it is also an issue of human life, which cannot be ignored."
The statement added: "President Karzai said if the lives of Afghans are not safe then strategic cooperation between the two countries will lose its meaning and concept."
Sources close to the meeting said the news release represented an accurate portrayal of the meeting.
"We take all human loss of life very seriously," said Gavin Sundwall, a U.S. Embassy spokesman.
An Afghan police official, citing initial reports, told CNN the Badghis incident, in the northwest, killed 14 civilians and wounded six others on Sunday.
NATO's International Security Assistance Force said an airstrike in the province killed three insurgents.
Separately, six civilians were killed in Helmand on Friday when an ISAF airstrike, called in by U.S. Marines under attack from insurgents, mistakenly hit a house containing children, the Helmand governor's office said in a statement.
The statement said that insurgents had attacked ISAF and Afghan police checkpoints in Sangin on Friday and an airstrike against insurgent positions "unintentionally" killed six civilians who were in the same house.
The statement said the dead included two boys, three girls and a woman. It added: "ISAF forces also confirmed the event and apologized and they promised to help with the remaining members of the family."
A spokesman for U.S. Marines in Helmand, Lt. Col. Stewart Upton, said in an e-mailed statement: "At this point in the investigation we are able to confirm the incident and will be formally apologizing in the next couple of days to the family. We are deeply saddened by any civilian deaths, and particularly regret incidents where civilians are killed as a result of actions by ISAF."
In eastern Afghanistan, attackers killed three U.S. soldiers Monday, a Western official said.
The deaths occurred just south of a base in Ghazni province when an explosion hit the vehicle the soldiers were traveling in, said the official who asked not to be identified because he is not authorized to discuss the incident with media outlets.
Two Americans were wounded as well, the official said.
The NATO-led force reported that three service members died in the bombing.
More than 1,900 Americans and another 1,000-plus allied troops have died in the 10-year conflict.
On Sunday, a NATO service member was shot to death by a gunman in an Afghan army uniform in southern Afghanistan, the allied command in Kabul reported.
The attacker was killed by coalition forces who returned fire, the NATO-led force reported.
The year has seen a number of attacks on coalition forces by Afghan forces or by insurgents who have disguised themselves as Afghan troops, fueling distrust at a critical period of the conflict.
In another attack Sunday, a roadside bomb struck a vehicle carrying U.S. troops in eastern Afghanistan, killing one American and wounding two, a Western official said. The bombing happened about 10 kilometers (6 miles) south of an outpost in Paktia province, near the Pakistani border, the official said.
CNN's Masoud Popalzai and Nick Paton Walsh in Kabul and Joe Sterling in Atlanta contributed to this report