PORTLAND, Maine (AP) Maine’s Republican senator has joined a bipartisan group of colleagues calling on the U.S. Food and Drug Administration to work harder to keep e-cigarettes out of the hands of children.

Sen. Susan Collins and others sent a letter to FDA Commissioner Stephen Hahn that says the commissioner should prioritize “much-needed public health oversight to these unregulated, addictive, and kid-friendly tobacco products.”

The senators wrote that millions of children are already vaping.