At least 20 people were killed and more than 60 wounded when a man in soldier’s uniform blew himself up at a military parade rehearsal in the Yemeni capital Sanaa on Monday, a police source said.
Yemen’s minister of defence and chief of staff were present but were unhurt, a military source said.
Yemen is home to al Qaeda in the Arabian Peninsula (AQAP), which the United States views as a major security threat, not only in the region but also on U.S. soil.
Militants have exploited political instability in Yemen to gain a foothold in a country paralysed for most of 2011 by protests that eventually unseated President Ali Abdullah Saleh.
A Reuters witness said the wounded were being ferried to hospital in taxis.
The parade was scheduled for Tuesday to mark Yemen’s national day and President Abd-Rabbu Mansour Hadi was due to attend.