A Palestinian human rights group has accused Hamas' internal security forces of mistreating prisoners detained in secret locations across the Gaza Strip.

The Palestinian Independent Commission says the detainees have been beaten, starved and subjected to psychological abuse.

But Hamas officials have denied the allegations, and on the eve of the Muslim holy month of Ramadan, ordered the release of nearly 100 political and criminal prisoners in a humanitarian gesture.

Al Jazeera's Ayman Mohyeldin has more from Gaza.