The New York Times reported that the United States this week significantly expanded the scope of its attacks on Iran and, at the same time as the practical collapse of a ceasefire, concerns about a return to a wider war have increased.

According to the newspaper, over two days U.S. forces targeted about 170 sites, including air defense systems, missile and drone storage facilities, and logistics infrastructure.

Washington has said the goal of these operations is to reduce the Islamic Republic’s ability to threaten shipping in the Strait of Hormuz.

The New York Times wrote that the attacks began after the Islamic Republic’s attack on commercial vessels in the Strait of Hormuz, and that Tehran, in response, targeted U.S. bases in Qatar, Bahrain, and Kuwait.

The newspaper added that the escalation of hostilities has increased the price of oil, while at the same time diplomatic efforts—especially with Qatar acting as mediator—to prevent the crisis from expanding