Cotton was charged by Hagerstown Fire Marshal Tom Brown on Friday.
On Saturday, Brown said Cotton's name surfaced in interviews with people referred to him by police. Brown said these sources told him
that Cotton set the fire as a prank because he "had nothing better to do.''
The fire destroyed the restaurant and left at least six employees temporarily without jobs.
The fire was started in the rear of the restaurant at 757 Dual Highway, authorities said.
Brown said he obtained a warrant for Cotton's arrest after interviewing witnesses.
Brown called Massy Hirai, owner of the restaurant, to tell him of Cotton's arrest. Hirai said Saturday the call was "good news.''
"I'm happy and pleased that they caught somebody," he said.
Hirai said he expects to start construction on a new restaurant at the old Dual Highway site as soon as he settles with his insurance company.
The restaurant moved to temporary quarters in the Dagmar Hotel building on the corner of Summit Avenue and Antietam Street downtown late last month, Hirai said.
He said his lunch business at the downtown location is about as good as it was at the old restaurant. "The dinner business is not so good. I don't have a hibachi here. That's about half of my business."
Hirai said his customers have been supportive since the fire.
"We have had so many calls, so many cards and flowers. I was born in Japan, but Hagerstown is my hometown now," he said.
The House of Kobe originally opened in the Dagmar Hotel building in 1981. It moved to the Dual Highway site 15 years ago, Hirai said.
He opened a House of Kobe restaurant in Frederick in July.