Hundreds of Somali refugees are being forced at gunpoint to join rebels fighting in northern Yemen, a Somali diplomat in Aden has told the BBC.
Hussein Haji Ahmed said they were being intercepted in mountainous territory crossing into Saudi Arabia.
“The refugees have told me that those who refused to join the rebellion were executed,” he said.
Both the authorities in Yemen and Saudi Arabia have alleged that Somalis have been fighting with Houthi rebels.
More than 16,000 Somali refugees have fled to Yemen in recent years to escape the civil war in their country, making the dangerous sea crossing in fishing boats.
Correspondents say some try to make their way to Saudi Arabia in search of better opportunities, paying trackers to take them over the dangerous terrain.
Mr Ahmed told the BBC Somali Service that refugees who made it across the border into Saudi territory were sometimes turned back by security forces, leaving them vulnerable to the rebels.
The Houthi rebels are seeking greater autonomy for their Zaydi Shia community in northern Yemen, and have been fighting the government since 2004.
The Zaydi community are a minority in Yemen, but make up the majority in the north of the country.
The government launched a fresh offensive in August 2009, which precipitated a new wave of intense fighting.
Last month Saudi forces began air and artillery strikes on Yemen after the rebels killed a border guard in a raid.