The United States last week secretly shipped a new long-range missile system to Ukraine, and Ukrainian forces immediately used the weapons to attack a Russian military airfield in Crimea last Wednesday and Russian troops in the country’s southeast overnight on Tuesday, according to a senior U.S. official.

The United States had previously supplied Ukraine with a version of the Army Tactical Missile Systems — known as ATACMS — armed with wide-spreading cluster munitions that can travel 100 miles.

But Ukraine has long coveted the system’s longer-range version, with a range of about 190 miles, which can reach deeper into occupied Ukraine, including Crimea, a hub of Russian air and ground forces, and supply nodes for Moscow’s forces in the country’s southeast.

Overnight Tuesday, Ukraine used the longer-range missiles to strike Russian troops in the port city of Berdiansk on the Sea of Azov, the senior U.S. official said, speaking on the condition of anonymity to discuss operational matters.

Last Wednesday, social media accounts in Ukraine reported large fires and explosions at a military airfield in Dzhankoi, Crimea, which the senior administration official said was also a long-range ATACMS target. In an address that evening, President Volodymyr Zelensky thanked Gen. Oleksandr Syrsky, the top Ukrainian commander, but did not elaborate on the attack.

In a major policy shift, President Biden secretly approved the decision to send more than 100 of the longer-range missiles in mid-February, the senior U.S. official said, as well as more of the cluster munition variant. They were part of a $300 million shipment of weapons to Ukraine in March, the first new aid package for the country since funding ran out in late December.