WASHINGTON — The United States imposed sanctions on five Russian individuals on Wednesday, including the leader of the Republic of Chechnya, for alleged human rights abuses and involvement in criminal conspiracies, a sign that the Trump administration is ratcheting up pressure on Russia.

The move, which comes despite a more accommodating tone that President Trump has struck with President Vladimir V. Putin of Russia, blocks property investments that the individuals hold in the United States and forbids Americans from engaging in financial transactions with them.

The Treasury Department unveiled the sanctions under the authority of the 2012 Magnitsky Act, an American law that freezes the assets — held in the United States — by Russian officials responsible for human rights abuses, and bars them from receiving American visas. The law was named after Sergei L. Magnitsky, a Russian lawyer who died in pretrial detention after exposing a $230 million tax-theft scam plotted by Russian officials.

“Treasury remains committed to holding accountable those involved in the Sergei Magnitsky affair, including those with a role in the criminal conspiracy and fraud scheme that he uncovered,” said John E. Smith, director of Treasury’s Office of Foreign Assets Control. “We will continue to use the Magnitsky Act to aggressively target gross violators of human rights in Russia, including individuals responsible for extrajudicial killings, torture and other despicable acts.”