Yemen faces a resurgence of al-Qaeda as well as other security challenges
Thirty-four suspected al-Qaeda militants have been killed and 17 arrested by security forces, the Yemeni defence ministry said.
The militants had allegedly been planning multiple suicide attacks, with eight of them preparing explosive vests, Reuters news agency reported.
The operations were carried out in Abyan province in the south and in Arhab, north of the capital Sanaa.
The resurgence of al-Qaeda in Yemen has raised concern in the region.
Officials have indicated that the operations were considered a major success against al-Qaeda.
The group was planning a number of suicide attacks against foreign and local targets, they say.
Airforce jets and soldiers hit training camps and hideouts early on Thursday, disrupting plans for attacks on domestic and foreign interests in Yemen, including schools, according to the ministry-linked website sep26.net.
The organisation has carried out frequent attacks in Yemen in recent months, generally against relatively low-level targets in the provinces such as local security officials.
The US concerns about al-Qaeda in Yemen stem partly from the fact that the government in Sanaa has so many other security issues to worry about, says the BBC's Owen Bennett-Jones in Sanaa.
They include a civil war in the north of the country, and frequent armed pro-independence protests in the south.
'Thousands of jihadis'
Yemen has long been an ideal base for jihadists, BBC Middle East analyst Roger Hardy says.
It is not just the ancestral home of the al-Qaeda leader Osama Bin Laden. With its rugged mountains and traditionally weak central authority, it is terrain well suited to militant groups looking for hiding places and training camps.
Large numbers of Yemenis fought Soviet troops in Afghanistan in the 1980s - and today Yemenis comprise the largest group of prisoners still being held by the Americans in Guantanamo Bay.
Last year the Yemeni foreign minister estimated there were over a thousand jihadi fighters in the country.
Al-Qaeda militants have carried out a string of suicide attacks over the last two years against targets including the US embassy and Western tourists.
They have also used the country as a base from which to attack neighbouring Saudi Arabia.
While the authorities insist they're doing everything they can to crush the jihadist movement, analysts believe that some radical Islamists have friends in high places who turn a blind eye to their activities, our BBC analyst Roger Hardy says .