It is being described as the largest explosion in more than three weeks of Saudi-led airstrikes in Yemen.
Between 95 and 98 percent of the capabilities of the Houthi militia have been neutralised
Civilians are reported to be among at least 30 people killed in an attack on a Scud missile base controlled by Houthi rebels in the capital, Sanaa.
Hundreds are reported to have been wounded in the latest bombing.
A Saudi military spokesman, Brigadier General Ahmed Asseri, told a media conference:
“In terms of air defences, we can confirm that between 95 and 98 percent of the capabilities of the Houthi militia have been neutralised and this was previously under the control of the Yemeni army.
“Some short-range artillery remains in use but this won’t affect our operations,” he said.
But the head of the Iran-allied Houthi rebels, who are fighting alongside army units loyal to ex-president Ali Abdullah Saleh, has vowed never to surrender.
Saudi Arabia is leading an alliance of Sunni Arab countries, supporting the exiled president Abd-Rabbu Mansour Hadi.
Meanwhile, as charities do their best to get humanitarian supplies through to civilians, Oxfam condemned a Saudi airstrike that hit one of its stores containing supplies.