A Palestinian boy was killed on Monday afternoon when Israeli soldiers fired at residents trying to cross Abu Holy checkpoint in the Gaza Strip, and a 10-year-old girl died Monday in a separate incident, according to a Palestinian medical source in Gaza.

The shootings took place as soldiers continued the closure of the al-Matahin and Abu Holy checkpoints, which was imposed four days ago. The closures of the key checkpoints divide the Gaza Strip into three parts.

The boy, identified as Raghib abdul-Rahman al-Masry, was seriously injured when soldiers fired at hundreds of residents trying to cross the checkpoints to get back to their homes. He was taken to al-Aqsa Hospital in Dir al-Balah, where he died of his wounds.

The 10-year-old girl, identified as Aida Dahgmash, was killed Monday as a result of an explosion at a home in the al-Sabra neighborhood in Gaza city. She died instantly, according to a medical source at Dar al-Shifa hospital in Gaza. Two of her brothers sustained wounds to several parts of their bodies.

The causes of the explosion are still unknown, according to a  Palestinian security source, but witnesses reported observing Israeli planes hovering over the area before the explosion took place. 

In another incident, at least three residents were injured after a huge explosion shook Khan Younis refugee camp in Khan Younis, in the southern part of the Gaza Strip.

The injured men are believed to be members of the military wing of Hamas.

According to an initial investigation carried out by Palestinian security agencies, the three were injured when a homemade shell exploded while they were attempting to fire it at a nearby Israeli settlement.