(AP) — Authorities in China’s financial hub of Shanghai have quarantined 186 people and conducted coronavirus tests on more than 8,000 after a freight handler at the city’s main international airport tested positive for the virus. The city government said Tuesday that no additional cases have been found. It remains unclear how the 51-year-old man contracted the virus, which has largely spared the sprawling metropolis. In the northern port city of Tianjin, more than 77,000 people have been tested after a locally transmitted case was reported there on Monday. That case was believed to be linked to a cold storage warehouse, reinforcing suspicions that the virus may be spreading to victims from frozen food packaging.