The authorities did not immediately report any deaths or injuries in the fresh attacks against symbols of authority in and around South America's largest city on Monday.
However, the Agencia Estado news wire service reported that police killed two suspects, wounded one and took another prisoner.
Two bystanders reportedly suffered minor injuries when a molotov cocktail was thrown at a supermarket.
A large explosion damaged the front of a state justice ministry in the city's centre and destroyed computers and other equipment inside, with the force of the blast blowing out windows of neighbouring buildings as high as the sixth floor.
Bullets were fired through windows of a nearby state finance ministry building, and two suspects opened fire at a police station from a car in a pre-dawn attack before abandoning the vehicle and fleeing, Agencia Estado reported.
Criminals also set fire to at least at least 10 banks, petrol stations and a supermarket in the attacks before dawn, Brazilian media reported.
The press office for Sao Paulo's state public safety department confirmed that various attacks occurred in the early morning hours.
At least 15 buses were torched in and around Sao Paulo, and two suspects were arrested, the Agencia Estado and Globo TV reported.
A gang launched attacks inside
prisons in May
In previous attacks, criminals torched scores of busses, prompting millions of Sao Paulo residents who depend on the bus service to stay home.
Bus service was suspended in Jundiai, and some lines were not running in Sao Paulo after the attacks.
But there were no signs that the attacks were having as much as an impact on commerce as the May attacks launched by the gang - when the city shut down altogether as residents stayed home and pulled their children from school.
Residents were outraged at the violence, demanding that police take tough action to restore order.
"We are living in constant fear of going out to do what you have to do every day," said Emilio Sousa da Silva, a 68-year-old cheese vendor at a market in the city centre.
"I think the cops are being too soft on criminals and they should be tougher. You're not going to hear complaints from me if bodies of the criminals start showing up."
During the May outbreak, the First Capital Command gang launched attacks on Sao Paulo's streets and inside dozens of prisons that prompted a week of violence, killing nearly 200 prison guards, criminals, jail inmates and bystanders.
Another 100 attacks from July 11-15 left at least six people dead.