New satellite images appeared to show that at least seven fighter planes at a Russian base in Crimea had blown up, despite Russian claims that no aircraft were damaged in explosions this week.

The images released Wednesday by Planet Labs PBC, a U.S. Earth imaging company, also showed charred grassland and several craters near the tarmac.

The Ukrainian air force said Wednesday that nine Russian warplanes were destroyed Tuesday in multiple massive explosions that also killed one person and wounded 14 others. Russia sought to downplay the blasts and said several munitions at the base caught fire and blew up.

But Oleksiy Arestovych, Ukrainian presidential adviser, said that the explosions were either caused by Ukrainian-made long-range weapons or by Ukrainian guerrillas operating in Crimea. Ukraine has stopped short of publicly claiming responsibility for the explosions, which also knocked out windows, damaged nearby apartment buildings and sent tourists fleeing.