DAMASCUS, Syria, Aug. 15 (UPI) -- Part of a Scud missile jointly developed by North Korea, Syria and Iran landed in a Syrian market in May, killing more than 20 people, a source said.

The missile, one of two developed by the three countries, strayed off course and landed in the market in Manbig, near the border with Turkey in northern Syria, Kyodo News reported, quoting a Western diplomatic source.

Military officials, who blocked access to the area to recover what was left of the missile, told residents there had been a gas explosion, Kyodo said. More than 60 people were injured, the news service reported.

A Mideastern military source said a problem with the guidance systems caused both missiles to go astray.

The other missile may have landed in a border area between Syria and Iraq, the diplomatic source said.

The launches were from southwestern Syria.

Kyodo reported the three countries are cooperating in trying to improve Scud missiles, developed by the Soviet Union during the Cold War.

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