Crude oil futures surged Thursday evening amid a still-ongoing Israeli attack on Iran that saw the leader of the Islamic Revolutionary Guard Corps reportedly killed.

Brent crude rose 9.3% while other metrics rose as high as 13%, according to CNBC. The Israeli targets were reportedly related to the Iranian nuclear program and there do not appear to have been strikes on any refineries as of press time.

The U.S. has denied involvement in the strike and warned Iran against retaliating against American forces in the region. As of press time, Iranian media outlets have discussed the prospect of a formal declaration of war against Israel.