At least seven people have died after gunmen opened fire at two checkpoints near the presidential palace and the intelligence building in Yemen's capital, Sanaa.
Four soldiers and three gunmen were killed in the attacks on Friday, said Al Jazeera's Hashem Ahelbarra, reporting from the capital.
"There's a deployment of security forces. They're blocking main roads in the capital. They have just intercepted a car packed with explosives on its way to the capital, Sanaa," our correspondent said.
"Security forces said that this was planned by al-Qaeda to start suicide bombing attacks to retaliate against the army's offensive, which is taking place in the southern part of the country. The atmosphere is very tense here in the capital " he said.
Al-Qaeda fighters also ambushed the Yemeni defence minister's motorcade on Friday, killing at least three and wounding two others, according to security and military officials.
|The defence minister was on his way back from visiting a recaptured al-Qaeda base [AP]
The attack happened as Mohamed Nasser Ahmad, the defence minister, Ali Hassan al-Ahmadi, the intelligence chief, and Awad Majwar al-Awlaqi, the military police chief, were travelling from Abyan province to Shabwa province, a military source said.
They were returning from a visit to an al-Qaeda base that had been recaptured by the military.
The minister and two other security officials were not harmed in the ambush.
Friday's attacks came amid rising tensions in the capital, Sanaa, where a bombing wounded 11 police officers hours after security forces killed an al-Qaeda commander.
Yemen's army launched a major offensive on April 29 against al-Qaeda in the Arabian Peninsula (AQAP) strongholds in three provinces in the south and claimed it had inflicted heavy losses on the group's fighters.
In a statement published earlier on Friday, the defence minister vowed to crush al-Qaeda fighters in Yemen, saying their end will come soon.
Sanaa has been on alert for days and tensions rose after the army announced troops had entered Azzan, a major AQAP stronghold in Shabwa province.
The US closed its embassy in the capital on Thursday as a precautionary measure due to fears that al-Qaeda might retaliate against the military's recent crackdowns on the organisation.
That same night, security forces also killed Shayef Mohammed Saeed al-Shabwani, an al-Qaeda commander suspected of masterminding the abduction of Western diplomats.
Shabwani was "one of al-Qaeda's most dangerous and wanted commanders," a security forces spokesman said, adding that he was also involved in killing Yemeni policemen.
Security forces arrested on Friday two men holding French citizenship who were members of an al-Qaeda cell in the country's eastern Hadramout province, an official security source told the Reuters news agency.
The two men were identified as Mourad Abdulla Abad and Taha al-Issawi, both of Tunisian origin but holding French citizenship.