According to the Sky News Arabia television channel, the Houthi rebels shelled residential areas in the city of Taiz less than an hour after the ceasefire took force.
The Almayadeen television channel in turn reported that the coalition did not stop bombing rebel positions. According to the channel, the northern Harad region not far from the border with Saudi Arabia was hit by three airstrikes after 12:00 GMT.
There have been no statements on the issue from either side so far.
Yemen has been engulfed in a violent conflict between the government headed by Hadi and the Houthi movement, the country’s main opposition force backed by army units loyal to former Yemeni President Ali Abdullah Saleh.
Since March 2015, the Saudi-led coalition of mostly Persian Gulf countries has been carrying out airstrikes against the Houthis at Hadi's request.