Yemeni authorities said on Monday they had tightened security around the city of Taez, a day after an American was shot dead there in an attack claimed by Al-Qaeda.
The top security commission in Yemen's second city met in the wake of Sunday's attack and agreed to reinforce policing, according to Saba state news agency.
The measures include a ban on carrying weapons in the city, as well as reducing the time during which motorbikes are allowed to circulate, it said.
Two gunmen riding a motorbike on Sunday shot dead the deputy director of the International Training Development Centre (ITDC), a US citizen, in the Sena neighbourhood.
A statement attributed to Al-Qaeda affiliates in Yemen claimed responsibility for the attack, saying the man had been proselytising for Christianity.
ITDC director Waldemar Braun denied the charge of proselytising and named the victim as Joel Shrum, saying he was a development worker.
"Unfortunately, Mr. Shrum has been accused of being a part of proselytising campaign, but the staff of ITDC, which consists of Muslims and Christians working together, has continually focused on human development, skill transfer and community development," Braun said in a statement.
He described Shrum as a "very professional employee who highly respected the Islamic religion."
The US embassy in Sanaa said on Sunday it did not have any information about the killing and that it was investigating the report.
The United States says the Yemen-based Al-Qaeda in the Arabian Peninsula, or AQAP, is the most active branch of the global extremist network.
Sunday's attack came two days after an official said suspected Al-Qaeda gunmen abducted a Swiss woman, also a teacher at a language school, in the Red Sea port of Hodeida and moved her to the restive province of Shabwa farther to the east.