A third Bahraini serviceman died on Wednesday following a Houthi drone attack on Monday against forces of the Saudi-led coalition in Saudi Arabia near the border with Yemen, Bahrain’s state news agency said.

Yemen’s Iran-aligned Houthi movement has battled the Saudi-led coalition since 2015 in a conflict that has killed hundreds of thousands and left 80 percent of the population dependent on aid.

The drone attack represents a major escalation after more than a year of relative calm in Yemen as peace efforts gain momentum. It could jeopardize talks between Saudi and Houthi officials who have just held another round of negotiations on a potential agreement toward ending the conflict.