Sen. John Boozman (R-Ark.). (Jeffrey MacMillan/For The Washington Post) Sen. John Boozman (R-Ark.). (Jeffrey MacMillan/For The Post)

Updated 3:31 p.m.

Sen. John Boozman (R-Ark.) has undergone emergency heart surgery in Arkansas after suffering pain in his chest and arm overnight, according to his office.

Doctors say the 63-year old senator "responded well to the surgery and are monitoring his recovery," a statement from his office said Tuesday afternoon. The senator's family "has visited with him and are hopeful for a full recovery. The family is appreciative of the thoughts and prayers from well-wishers."

Initial reports from local news sources said Boozman had been transported by ambulance to Mercy Hospital Northwest Arkansas. The senator had been scheduled to speak Tuesday morning in Gravette, Ark., to commemorate the opening of the first stretch of a highway there.

A former House lawmaker, Boozman has served as Arkansas's junior senator since defeating Democrat Blanche Lincoln in 2010. He easily won an eight-candidate GOP primary that year.

Boozman's Arkansas colleague, Sen. Mark Pryor (D-Ark.) said via Twitter Tuesday that he is "Fortunate to call @JohnBoozman good friend & trusted colleague. Lifting up his family & friends in prayer. Wishes for a speedy recovery."

Senate Minority Leader Mitch McConnell (R-Ky.) also weighed in with good wishes, saying in a statement that "we all look forward to having him back at work. He is a fantastic Senator and a tireless advocate for Arkansas and the people he so proudly represents."