The UK-based Syrian Observatory for Human Rights (SOHR) said 21 of those reportedly killed on Sunday morning were children.
The village is in Deir al-Zour, one of the last provinces where Islamic State still holds territory.
Initially SOHR said 34 had been killed in strikes on residential buildings.
But the monitoring group's head told the AFP news agency it now believed the figure was higher.
"The toll increased after removing the debris in a long day of rescue operation," Rami Abdel Rahman said.