Bangladesh security forces have shot dead a Rohingya woman in a border town known as a gateway for smuggling meth pills from neighbouring Myanmar, officials said Sunday.

Rights activists said Rumana Akter, 20, was the first Rohingya woman to be killed in a clampdown by Bangladesh authorities against the narcotics trade.

She was one of three alleged smugglers killed in two separate incidents in Teknaf, which is close to refugee camps housing about one million Muslim Rohingya who have fled from Myanmar.

Teknaf is a hub for dealing in "yaba" — a methamphetamine-based stimulant that translates in Thai as "crazy medicine" — which has become popular in Bangladesh.

More than 300 people — including nearly 20 Rohingya — have been killed in the clampdown launched in May last year.

Impoverished Rohingya refugees are used by dealers to transport the drug from Myanmar, officials say. A military crackdown against the Rohingya in August 2017 sparked an exodus of 740,000 refugees to flee the country and join some 300,000 refugees already in camps in Bangladesh.

Border Guard Bangladesh (BGB) said the Rohingya woman was killed during a gunfight between security forces and armed smugglers on the Naf river, which acts as a border between Bangladesh and Myanmar.

BGB spokesman Shariful Islam told reporters the woman's body was found after a 15-minute gunbattle "along with 10,000 pieces of yaba and three sharp knives in her bag". Akter came from a refugee camp in Teknaf.

Rights activists questioned the death, saying the woman's name was not on a list of known drug traders kept by Bangladeshi law agencies.

Two alleged drug traders were killed by police in a separate incident in Teknaf late Saturday. Police said 10,000 pieces of yaba, six guns and 18 rounds of ammunition were found.

As part of clampdown Bangladesh authorities in October made yaba a class-A banned substance and parliament passed a law allowing the death penalty for dealing in the drug.