The same day, soldiers executed six other villagers, including a 72-year-old and his son. At a house under construction on the outskirts of the village where their bodies were found, I counted 16 bullet holes in the wall.

I was told about many more atrocities. In Mashamshan, a shell struck the home of the Yousef family on May 1, killing seven members and injuring several others. In Qoqfeen, a 5-year-old girl, Maryam Qaddi, was killed May 12 when a hail of bullets from army forces positioned across a valley hit her home. The attack injured her 10-year-old cousin and her 70-year-old aunt. Then there are the stories of torture told by those who have been detained. Those who escape have come away with broken bones, missing teeth, deep scars and open wounds from electric shocks and beatings. Detention and torture is the fate of anyone suspected of supporting the opposition in even the smallest way. Many victims used to be supportive of the government or were not politically active. Most are young.

Fearful of being detained or killed, most men stay away from army checkpoints. Such pervasive fear seems well-founded, judging by the increase in executions in recent months.

The world must send a clear message to Syria that these atrocities can’t go on. A monitoring mandate for the U.N. observer mission is a crucial first step to holding accountable those responsible for crimes against humanity.

Donatella Rovera is Amnesty International’s senior adviser on crisis response and has reported from numerous conflict zones on human rights violations since 1991. She has traveled inside Syria several times over the past two months.