Four Palestinians were killed Friday amid marches that have been ongoing since late March, according to The Associated Press.
The demonstrators are calling for the right for Palestinians and their descendants to return to what is now Israel. Hundreds of thousands of Palestinians fled or were forced out of their homes during the 1948 war that led to the creation of Israel.
Photos show protesters amid in heavy plumes of smoke as they burn tires and hurl objects toward Israeli forces near the border.
The protests, led by Hamas, are part of a series that organizers hope will culminate in a mass march on May 15.