The Kremlin has threatened the United States with retaliation for a Ukrainian strike on Crimea that killed at least four people and wounded more than 150 others. Russia has directly blamed the US for the attack, saying Kyiv used the missiles that were sent by Washington, while the US military provided it with data on targets. Russia also summoned the US ambassador to warn her of revenge. Meanwhile, Washington said it regrets any loss of life, adding that the weapons have been provided to Ukraine to defend its sovereign territory, including Crimea. Russia unilaterally annexed Crimea in 2014. However, most of the countries still consider it part of Ukraine.