Almost three years after the Houthis first garnered international attention by attacking ships off Yemen, the rebels have only increased their violent influence in the Middle East. Here's a primer on the group that could push the price of global oil even higher.

Houthis escalate attacks from Yemen to Saudi Arabia, threatening Red Sea shipping, Bab Al Mandab and global oil routes as Riyadh vows to defend its sovereignty.

The Houthis have also launched attacks on the strategically located Hanish Islands, further intensifying tensions in the region. | World News