The coalition has vowed to keep up the strikes until the Huthi rebels end their uprising against President Abedrabbo Mansour Hadi, who has fled to Saudi Arabia.
The fighting has sent tensions between Sunni Arab nations and Shiite Iran soaring, even as marathon nuclear talks between Tehran and world powers in Switzerland enter a crucial final phase.
The Huthis and their ally, former president Ali Abdullah Saleh, "decided with the support of Iran to destabilise Yemen," Saudi Foreign Minister Prince Saud al-Faisal said Tuesday.
"We are not warmongers but when they beat the drums of war we are ready," Saud told the Shura Council advisory body, according to its Twitter account.
Kuwait's Al-Watan newspaper launched a vitriolic attack against Tehran, describing the air strikes as "the biggest blow to Iran in decades".
The coalition campaign "raises hopes of a historic success for the Arabs and a rout of one of their worst enemies: the Persian state," added the daily.
- 'Day of terror' -
Huge blasts were heard overnight in Sanaa when coalition forces hit a missile depot belonging to the renegade Republican Guard, which is loyal to former strongman Saleh.
"Sanaa lived through a day of terror due to the continuous bombing from early Monday until this morning," said Assem al-Sabri, a 28-year-old resident.
"We couldn't sleep from the sounds of explosions," he told AFP.
The missile depot blast rocked a southwestern district of Sanaa and flames billowing from the site were seen by residents across most of the city.
"The bombing was the heaviest I have ever heard in my life. The explosions lit up the skies of Sanaa," said another resident, 30-year-old Amr al-Amrani.
Early Tuesday, air strikes targeted two camps held by Huthi rebels and allied Republican Guard soldiers in the southern town of Daleh.
Columns of smoke rose from the area, witnesses said.
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Coalition warplanes also raided an air base belonging to a Republican Guard brigade in the southwestern city of Taez, witnesses there said.
For the first time since the coalition operation began, warplanes also bombed renegade troops in the Shiite-populated city of Dhammar, a stronghold of the Huthi rebels south of Sanaa.
They also hit another arms depot north of the capital, according to witnesses.
- Trading blame -
After an air strike killed dozens of people at a camp for displaced people in northwest Yemen on Monday, the two sides traded accusations over the incident.
"The coalition was targeted by militiamen from a residential area and coalition planes had to respond" to the fire, coalition spokesman Ahmed Assiri told reporters in Riyadh.
"The Huthis are seeking to place their forces among the people and the coalition is doing everything it can to avoid civilian casualties."
The rebel-controlled health ministry condemned "the Saudi aggression on Yemen that left many innocent victims, children, women, and civilians".
The Huthis and allied renegade military units have overrun much of Yemen and prompted Hadi to flee what had been his last remaining refuge in Aden.
Dozens of people have been killed in several days of clashes in the city, and Hadi's aides have said he has no immediate plan to return there.
The coalition, which accuses Iran on backing the rebels, has imposed a sea blockade around Yemen.
Hadi has branded the Huthis the "puppet" of Tehran, and the prospect of an Iran-backed regime seizing the impoverished Arabian Peninsula state has alarmed many countries in the region.
Israeli Prime Minister Benjamin Netanyahu warned Western powers Monday that any nuclear deal struck in talks in the Swiss city of Lausanne would be seen as a reward for Tehran's "aggression" in Yemen.
Countries including Pakistan and China have evacuated nationals from the war-torn country.
Indian Prime Minister Narendra Modi on Monday asked Saudi King Salman for his support in efforts to evacuate some 4,000 stranded citizens, expressing "deep concern" for their welfare.