Dozens were killed and injured in clashes between pro-government fighters and Houthi militants in Yemen's city of Taiz, local sources said on Sunday.
The casualties included civilians and children as Houthi militants were firing rockets on residences, the sources said.
On Saturday, the Houthi militant group deployed reinforcements and rocket launchers into Taiz.
The militants have been shelling districts including Sharaab and Sabir Mountain with rockets all day, they added.
The clashes continued in Taiz in the past few days despite a five-day humanitarian ceasefire which guaranteed only a halt to Saudi-led airstrikes on the Houthi militants.
Today, clashes between pro-government fighters and Houthi militants continued in other cities including Aden where the Houthis expanded their presence during the truce.
The Houthis have breached the ceasefire continuing violence in several cities. They are also denying access to aid amid outcry the aid flowing into the country is not sufficient.
Today, the new UN envoy to Yemen Ismail Ould Chiekh called for extending the ceasefire for more days at least.
At the Riyadh conference for saving Yemen and building it a federal state, Cheikh urged on all parties to stop violence and cooperate with relief organisations so that aid reaches those affected by violence.
The Houthi group boycotted the conference.