At least 16 people were killed in an Israeli bombing of a school housing refugees in the al-Nuseirat camp in the central Gaza Strip, according to the Hamas Health Ministry.
According to the same source, the number of injured exceeds 50, although there are fears that the death toll will rise.
The Israeli military said it was investigating the reports.
The Al-Nuseirat camp is one of the eight historic camps in the Gaza Strip and was today the target of heavy bombardments by the Israeli army.
Earlier, an airstrike on a residence in the camp killed at least 10 people and injured many, hospital sources said.
In its daily tally of casualties, the Gaza Health Ministry announced that at least 29 Palestinians were killed by Israeli strikes in the past 24 hours and 100 were injured.