Patrolling the Saudi-Yemeni border with Saudi troops

A Saudi-led bombing campaign has been targeting anti-government Houthi rebels in Yemen since March.

Rebel leader Abdul Malik al-Houthi has vowed that his forces will resist the on-going campaign.

Hundreds of people have died as rebels and government forces have clashed in the country.

Jeremy Bowen, BBC Middle East Editor, has travelled with the Saudi Arabian military down to the southern border with Yemen.