U.S. efforts to promote the expansion of India’s solar industry may have opened a back door to components made with forced labor in China.

India’s largest solar producer, Waaree Energies, has sent millions of panels to the U.S. made with components from a Chinese company whose products were repeatedly denied entry to the U.S. market over concerns about forced labor, an examination of Indian and U.S. import records shows.

Those components, solar cells produced by China’s Longi Green Energy Technology at plants in Malaysia and Vietnam, are used in Waaree panels blanketing solar farms in Texas and other states.