Palestinians have clashed with Egyptian police at the Rafah border crossing between Egypt and the Gaza Strip.
Witnesses and police say angry Palestinians threw stones at border guards after only a limited number of them were allowed to enter Egypt. At least six police were injured.
Police used water cannons against the crowd.
Egypt opened the crossing on Tuesday to allow entry by Palestinians who need medical treatment not available in Gaza.
Egypt has kept the Rafah crossing closed since the militant group Hamas seized control of Gaza more than a year ago.
In January, Hamas militants blew open the border wall, allowing thousands of Palestinians to stream into Egypt to buy goods that are scarce in Gaza, which is subject to an Israeli blockade.
Egypt sealed the border breach about two weeks later.
Some information for this report was provided by AP and Reuters.