A woman walks with her son past shops in Gaza city on May 14, 2023. (PHOTO / AFP)

JERUSALEM - Gaza militants fired a rocket at southern Israel on Sunday, a day after an Egyptian-mediated ceasefire ended five days of cross-border fighting, and Palestinian militant groups said the launch had been a "technical error".

A source from the joint operations room of militant groups in Gaza said the rocket was launched "due to a technical error"

Shortly afterwards, explosions were heard in northern Gaza and the Palestinians reported that a militant outpost had been struck by Israel. There was no immediate comment from the Israeli military.

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Just before sundown, sirens went of in Israeli towns near the border, sending residents running for shelter, about 20 hours after the ceasefire had taken effect.

Israel's military said a single rocket fired from Gaza struck an open area.

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A source from the joint operations room of militant groups in Gaza said the rocket was launched "due to a technical error."

No injuries were reported on either side.