Air strikes have been reported in two cities in Yemen.
Witnesses and governing Houthi rebels said an airport and military base were targeted in the capital Sanaa, while a power station in the western port city of Hudaydah was also hit, the AFP news agency reported.
Houthi TV blamed the strikes on Israel, which has not commented on the reports.
Casualties were not clear from initial reports. In recent days Israel has warned it was preparing a major attack on the Houthis after the group fired drones and missiles at it.