The airstrikes on the port city come a day after a drone strike by the Yemeni group killed one person in Tel Aviv.
The Israeli military said it carried out strikes on Yemen's Red Sea port city of Hodeidah in response to attacks by the Houthi group.
Saturday's airstrikes came a day after the Houthis claimed responsibility for a drone attack that killed one person in Tel Aviv and wounded 10 others.
Houthi-affiliated Al Masirah TV channel said the Israeli strike targeted oil storage facilities and a power plant in Hodeidah, sparking a fire in the area. The outlet cited health officials as saying the airstrikes caused casualties, including fatalities, without specifying a number.
But the Israeli military said the attack hit “military targets” in Yemen.
The Israeli airstrikes are Israel's first known direct attack on the Houthis since the start of the Gaza war. The attack comes amid growing fears of an escalation of violence in the Middle East.
Houthi spokesman Mohammed Abdel Salam said the “brutal Israeli aggression against Yemen” is aimed at “putting pressure on Yemen to stop supporting Gaza, which is a dream that will not come true.”
He added that the attack “will only increase the resolve of the Yemeni people and their brave armed forces.”
Hamas was also quick to condemn the Israeli attack. “The occupation state will undoubtedly be burned by the fire that started today in Hodeidah, and the increasing Zionist crimes will change the whole equation,” Izzat al-Rishq, a member of the Palestinian group’s political bureau, said in a statement.
But Israeli Defense Minister Yaov Gallant hailed the attack as a warning to Israel's adversaries.
“The fire currently burning in Hodeidah is visible across the Middle East and its significance is clear,” Gallant said. “The Houthis have attacked us more than 200 times. The first time they harmed an Israeli citizen, we attacked them. And we will do so wherever necessary.”
The Houthis, allies of Iran and presenting themselves as Yemen's official armed forces, have been attacking shipping lanes in the Red Sea in a campaign they say is aimed at pressuring Israel to end its war in Gaza, which has killed more than 38,900 Palestinians.
The Yemeni group has also launched ballistic missiles and drones at Israel, most of which have been intercepted.
But early on Friday, a Houthi drone packed with explosives evaded Israeli air defenses and attacked a building in Tel Aviv in what was seen as a major security breach in Israel.
Israeli officials had vowed to respond. Gallant promised in a message to the Houthis on Friday that Israel would “get even” with anyone who harms its security.
The United States and Britain have been carrying out airstrikes in Yemen for months in response to Houthi attacks in the Red Sea, but the military campaign has failed to stop the Yemeni group's attacks.
Al Jazeera's Hamdah Salhut said the latest developments were likely to test the Israeli military, which was “already stretched to its limits” amid fears of an all-out regional war.
Salhut noted that Israeli reservists are operating in both the north and south of the country against Hamas in Gaza and Hezbollah in Lebanon respectively.
“If the Air Force has to be deployed to more parts of the Middle East, such as Yemen, it is difficult to say exactly how they will handle it when they are still looking to recruit more people for the army,” he said. “It is a lot of pressure for the Israelis, as another front has opened this morning.”
