Local security forces in Afghanistan have made nine arrests in connection with recent bombings that killed nearly 140 people, the governor of Kandahar confirmed Thursday.

The men were arrested Wednesday in Kandahar City and the Arghandab district.

"These men are believed to have been responsible for the worst spade of attacks Afghanistan has seen since 2001," The Globe and Mail's Graeme Smith told CTV's Canada AM on Thursday.

Four guns, bomb-making materials, motorcycles and other documents were seized by officials, said Gov. Asadullah Khalid.

Khalid said local civilians helped the government identify four of the suspects.

"We were following these terrorists for a long time,'' Khalid told The Canadian Press. "We were aware they were going to do something.''

On Sunday, more than 100 people were killed after a suicide bomber blew himself up at a dog fighting festival. Another 38 people died Monday following a suicide bombing in the border city of Spin Boldak.

Four Canadians were hurt in that attack.

A third blast occurred on Tuesday inside Kandahar City where at least one civilian was killed.

Smith said the Taliban have recently been trying "large, spectacular attacks."

"Analysts believe there are some more extreme elements, some al Qaeda-linked elements, that are starting to assert themselves and become more prominent (within the Taliban)," he said.

NATO Secretary General Jaap de Hoop Scheffer said Thursday that the militants are trying to influence public opinion in Afghanistan and among NATO countries that have troops in the country.

"Let's not give them a ticket to ride," de Hoop Scheffer said of the bombers during a joint news conference with Afghan President Hamid Karzai.

With files from The Associated Press