A drone attack by Yemen's Houthi rebels killed a Bahraini officer and soldier who were patrolling Saudi Arabia's southern border early Monday, Bahrain's military command said.

The statement, carried by the official Bahrain News Agency, says "a number" of Bahraini soldiers were also wounded in the attack, without elaborating.

The tiny island nation of Bahrain is a close ally of Saudi Arabia, which has been at war with the Iran-aligned Houthi rebels for several years. A cease-fire had largely stopped the violence, and the two sides have appeared close to a peace agreement in recent months.

It was unclear if the attack would derail those efforts or prompt retaliation by Saudi Arabia and its allies. There was no immediate comment from the Houthis or Saudi Arabia.

"This terrorist attack was carried out by the Houthis, who sent aircraft targeting the position of the Bahraini guards on the southern border of the kingdom of Saudi Arabia despite the halt of military operations between the warring sides in Yemen," the Bahraini military statement said.

Yemen's war began in 2014 when the Houthis swept down from their northern stronghold and seized the capital, Sanaa, along with much of the country's north. In response, a Saudi-led coalition intervened in 2015 to try to restore the internationally recognized government to power.

The fighting soon devolved into a stalemated proxy war between Saudi Arabia and Iran, causing widespread hunger and misery in Yemen, which even before the conflict had been the Arab world's poorest country.

Saudi Arabia and Iran restored diplomatic relations earlier this year in a deal brokered by China, further raising hopes for an end to Yemen's conflict. Earlier this month, Saudi Arabia welcomed a Houthi delegation for peace talks, saying the negotiations had "positive results."

A U.N.-brokered cease-fire had already largely halted the violence, and Yemen has seen only sporadic clashes since the truce expired nearly a year ago. But diplomats have warned that the situation remains volatile.

Yemen's internationally recognized government condemned the attack. Foreign Minister Ahmed Bin Mubarak said he spoke by phone with Bahrain's chief diplomat, Abdullatif al-Zayani, offering his condolences and solidarity with Bahrain.

Bahrain, an island nation in the Persian Gulf off the coast of Saudi Arabia, was rocked by an uprising in 2011 inspired by the Arab Spring protests elsewhere in the region. Many from the country's Shiite majority called for the overthrow of Bahrain's Sunni monarchy. Bahrain quashed the revolt with aid from Saudi Arabia and the United Arab Emirates, and blamed much of the unrest on Shiite-majority Iran.