The Guangzhou Baiyun District People's Procuratorate in the Guangdong provincial capital has indicted a Japanese senator on drug smuggling charges, according to Japan's Kyodo News.

A trial is expected to be held in the Guangzhou intermediate court, but when it will begin is unknown, local media reported.

The Guangzhou Baiyun District People's Procuratorate did not comment on the case on Tuesday.

Takuma Sakuragi, 70, a member of the Inazawa municipal assembly in Aichi Prefecture, was detained by police after more than 3 kilograms of methamphetamine, which is commonly known as "ice", was found in his luggage during a baggage check at Guangzhou Baiyun International Airport in October 2013.

Sakuragi was on his way home via Shanghai and had planned to take Flight CZ3613 to Shanghai from Guangzhou when he was detained.

Local officials informed Japan's consulate general in Guangzhou, in line with regulations and international practices, on Nov 1, according to a statement from the procuratorate.

The Guangzhou Baiyun District People's Procuratorate officially approved the arrest of the Japanese assemblyman in December, the statement said.

Two more suspects in the case were detained on Nov 18 and 19.

After Sakuragi was detained, he denied trafficking drugs, saying he was helping a Nigerian friend take luggage to Shanghai.

According to the relevant criminal laws, in China, the seizure of 50 grams or more of heroin or methamphetamine can result in the use of the death penalty, and this applies to both Chinese citizens and foreigners.

China executed a convicted Japanese drug trafficker in the northeast city of Dalian, Liaoning province, on July 26.

The unidentified 50-year-old was the fifth Japanese person to be executed in China since the two countries normalized relations in 1972.

The report said the man was found guilty of acting with another Japanese man to transport drugs from Dalian to Japan. It did not state when the case happened or what drugs were being carried.

The Dalian immediate court informed the Japanese Consulate General staff before the execution. The condemned man was allowed to meet with relatives before his execution.