Shares of gun makers rallied Monday, in the wake of what has been described as the deadliest mass shooting on U.S. soil.

Smith & Wesson parent American Outdoor Brands Corp.’s stock US:AOBC jumped 3.0% in afternoon trade. Volume topped 3.7 million shares, compared with the full-day average over the past 30 days of 2.1 million shares.

Sturm, Ruger & Co. Inc. shares RGR, +0.11% climbed 2.7% and Vista Outdoor Inc. shares VSTO, -0.21% ran up 1.8% toward a 6-week high.

Read: At least 58 killed and more than 515 injured in mass shooting at Las Vegas concert.

Analysts say the regulatory environment is among the biggest drivers of demand for guns, as fears of tighter regulation have boosted gun sales and share prices in the past. Since President Trump was elected, however, fears of tighter regulations have faded and share prices have dropped.

See also: Smith & Wesson’s stock drops as Trump’s surprise win saps demand.

In the latest quarter ending July, American Outdoor sales fell 38% from a year ago. In the quarters through June, sales declined 22% at Sturm, Ruger sales and 10% at Vista Outdoor.

American Outdoor’s stock had tumbled 46% since the election through Friday, and closed at a 2 ½-year low of $13.31 as recently as Sept. 11. Sturm, Ruger shares had shed 20% since the election, and had also hit a roughly 2 ½-year low in September. Vista Outdoor’s stock, which hit a record low in April, had plunged 40% since the election.

In contrast, the S&P 500 index SPX, -1.11% had run up 18% since the election.

American Outdoor was upgraded last week at Wedbush Securities, citing a survey suggesting demand was still strong, but buyers just lacked a sense of urgency.

In other market reactions to the mass shooting in Las Vegas, shares of casino operators MGM Resorts International MGM, -2.22% tumbled 5.4% in afternoon trade and Wynn Resorts Ltd. WYNN, -2.01% lost 1.3%, while Las Vegas Sands Corp.’s stock LVS, -0.16% gained 1.4%.

See also: The chilling warning raised within the Las Vegas crowd shortly before the killings.

Also read: These are the 10 deadliest mass shootings in U.S. history.