The heavy U.S. tariffs on other Asian countries have made China a more appealing option for companies scared to make a hasty decision amid upheaval in global trade.

Workers said poor-quality materials were used during construction by a Chinese developer as it sought to cut costs. Investigators also said they found substandard steel bars in the rubble.

The collapse of a 30-story building under construction was “not normal,” an engineering expert said. It was one of the biggest projects ever done by a Chinese state-owned company.

The State Department said it was “combating China’s efforts to pressure governments to forcibly return Uyghurs and other groups to China.”