GAZA - Twenty-one Palestinians were killed on Wednesday morning near an aid distribution center in Khan Younis in the southern Gaza Strip, said Gaza-based health authorities.

Among the dead, 15 were killed from suffocation due to the release of gases on the crowds and the subsequent stampede, said the health authorities in a statement.

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"For the first time, deaths have been recorded due to suffocation and severe stampede among citizens at aid distribution centers," it said.

According to the US-backed Gaza Humanitarian Foundation (GHF), one victim was stabbed "amid a chaotic and dangerous surge, driven by agitators in the crowd."

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"We have credible reason to believe that elements within the crowd - armed and affiliated with Hamas - deliberately fomented the unrest," said the GHF in a statement on social media.

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The GHF is operated by US security contractors and is approved by the Israeli government. The GHF has faced mounting criticism for poor management and operational chaos.