A series of intense Israeli airstrikes shook Yemen's rebel-held capital and a port city early Thursday and killed at least nine people, officials said, shortly after a Houthi missile targeted central Israel.

The strikes further escalate Israel’s campaign against the Iranian-backed Houthis and risks further escalating conflict.

Israel has said its fighter jets conducted a series of attacks against military targets in Yemen belonging to the Iran-backed Houthi movement.An Israeli military spokesman said the targets included Red Sea ports and energy infrastructure in the capital Sanaa.