Four suicide attackers have killed at least 30 in the southern city of Kandahar, according to the half-brother of Afghan President Hamid Karzai.
The four suicide bombers struck different parts of the city Saturday evening. The attacks collapsed buildings, officials said.
Ahmed Wali Karzai, a member of the Kandahar provincial council, said a main target of the Saturday night attacks was a prison, but no prisoners escaped. In June 2008 a suicide bomber blew apart the Kandahar prison gates and a nearby checkpost. That freed hundreds of prisoners, many of them suspected insurgents.
Karzai said a second explosion occurred close to the police headquarters, and casualties were reported at a wedding hall nearby.
Police officer Mohammad Nahim says at least four policemen were killed.
The explosions occurred near a hotel, a prison, a mosque and at an intersection in the city center, said Mohammad Shad Farooqi, deputy police chief in Kandahar province.
An unknown number of casualties were reported, said Zemarai Bashary, a Ministry of Interior spokesman. He said police and soldiers have secured the city.
Someone who contacted CBS News claiming to be a Taliban commander in Kandahar said militants have attacked the police headquarters, a hospital, jail, and the house of Karzai's brother.
The caller added that prisoners are escaping, and that fighting has erupted all over city, said CBS News' Sami Yousafzai.
Mayor Gulam Hamidi said several buildings collapsed, including houses and shops. "I am sending my equipment to help the police to try to dig through the rubble," he said.
His daughter, Ragina Hamidi, who runs a small business in Kandahar, said: "We are just staying in doors for our own safety."
Kandahar has a population of 800,000. It is the south's main commercial center and the major city in Kandahar province, the birthplace of the Taliban.
A Kandahar-based NGO worker told CBS News via cell phone that the situation in the city was tense, and that gunfire was heard near Karzai's brother's house.
Suliman Khan Firotan said that a big blast occurred at 8 p.m. local time, followed by three more blasts and heavy gunfire. "We rushed to basement of the house," Firotan told CBS. At 10 p.m., Firotan said, exchanges of gunfire were still heard between police and militants.