Heavy fighting occurred between Yemen rebels and loyalist forces on Saturday around the city Taez in spite of a 48-hour ceasefire announced by a Saudi-led coalition, fighting the insurgents began following US pressure.
A few hours after the ceasefire took effect at midday (0900 GMT), fighting still raged around the flashpoint southwestern city, where violence has killed dozens this week, despite clashes subsiding on several fronts.
Clashes were heaviest in the town of Salo, southeast of Taez, military sources said, reporting casualties on both sides.
Inside Taez itself, rebel rocket fired into a residential district killed one civilian and wounded two, the sources added.
Intermittent fighting was also reported in Nahm near the capital Sanaa, in Shabwa in the south and Sarwah to the east.
The ceasefire comes after a push by US Secretary of State John Kerry who this week met rebel representatives in Oman and also urged the government to come on board.
At first the government, which has deep reservations about a UN peace blueprint it believes undermines its authority, rejected the peace bid before later agreeing to observe it.
Yemen's government has come under huge pressure to back down in the face of an international outcry over the mounting civilian death toll from 20 months of conflict.
"There are international pressures to observe a ceasefire and to resume (peace) negotiations," a source close to the presidency, requesting anonymity.
The 48-hour truce could be extended if the rebels hold fire and allow aid into besieged loyalist enclaves, said a coalition statement carried by the official Saudi Press Agency.
More than 7,000 people have been killed in Yemen and nearly 37,000 wounded since the coalition intervention began in March 2015, the United Nations says.
"We really hope that the war will end. All Yemenis are very tired of the conflict," said Khaled al-Waysi, a resident of Sanaa.
Another resident, Sadeq Juhaifi, said: "We want one of the parties to be courageous enough to announce long-term peace, not just a two or one-day ceasefire."
An official document has been issued by the defence ministry ordering all pro-government forces to abide by the ceasefire, report violations, and reserve the right to respond to any rebel breaches.
A spokesman for forces allied to the Iran-backed Shiite Huthi rebels, Brigadier General Sharaf Luqman, confirmed that they would also abide by the ceasefire.