A string of bomb attacks targeting Thailand's crucial tourism industry have killed four people, The Telegraph quoted officials as saying on Friday.

Twin bombs exploded in the upscale resort of Hua Hin late on Thursday, killing one Thai woman and wounding more than 20 others, including nine foreign tourists, and were followed by two more on Friday morning that killed another person and injured three.

Two small bombs exploded in the tourist beach town of Patong on Phuket island and two more in Phang Nga, another tourist region north of Phuket, local police said. One Thai man was lightly wounded in Patong, police said.

Two more bombs were reported in the southern provinces of Trang and Surat Thani, each of blast killed one person.

Prime Minister Prayut Chan-O-Cha called for calm and said he did not know who was behind the attacks.

"The bombs are an attempt to create chaos and confusion," he told reporters. "We should not make people panic more."

Source: MENA