Geneva: Thirty African migrants, some of them among thousands deported by Saudi Arabia, have died in recent weeks along Yemen's border where a humanitarian crisis is growing, an aid agency said last Friday.

Saudi Arabia has been expelling illegal migrants, mainly from Ethiopia, Somalia or Sudan, who reach the oil-exporting kingdom after a long and hazardous journey across the Horn of Africa, seeking a better life in the Gulf or beyond, the International Organisation for Migration (IOM) said.

"An increasing number have been deported by Saudi Arabia and dumped at the border," IOM spokeswoman Jemini Pandya told a news briefing. "Thirty migrants have died in the past few weeks."

One was shot, another beaten to death and a third had died of kidney failure, but exact circumstances were unclear, she said, adding: "The morgue is now full."