Saudi Arabia said on Sunday it intercepted two missiles launched by Yemen’s Houthi militia over the capital Riyadh, as a Saudi-led coalition moved to wrest control of Yemen’s main port city from the Iran-aligned group, Reuters reports.

At least six loud blasts were heard and bright flashes were seen in the sky over the Saudi capital, a Reuters witness said. Shrapnel was spotted on a street in the diplomatic quarter where most embassies are located and many foreigners live.

“Saudi Royal Air Defence Forces intercepted and destroyed the missiles. Some of the debris of the intercepted missiles landed on residential areas, thankfully without causing any casualties,” coalition spokesman Turki al-Malki said in a statement.

Houthi-run al-Masirah television said Burkan missiles were fired at the Saudi defence ministry and other targets.

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The attack was the first to target Riyadh since the Saudi-led coalition launched an offensive on June 12 to capture Yemen’s Hodeidah port city, in the biggest battle of the war aimed at weakening the Houthis by cutting their main supply line.

The Houthis, who control most of Yemen including the capital Sanaa, have fired a series of missiles into the kingdom in recent months, part of a three-year-old conflict widely seen as a proxy battle between Saudi Arabia and Iran.

There was a heightened security presence and fire trucks in the diplomatic quarter following Sunday’s missile attack, which was the sixth on Riyadh since December.

“The longer the aggression and war continue, the greater our ballistic missile capabilities,” Al Mayadeen TV quoted Houthi spokesman Mohammed Abdul-Salam as saying.

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The Western-backed coalition intervened in Yemen’s war in 2015 to unseat the Houthis and restore the internationally-recognised government in exile.

Riyadh has accused the Houthis of using the port to smuggle Iranian-made weapons, including missiles — accusations denied by the group and Tehran.