MANILA, Philippines - The United Kingdom has warned its nationals against using or trading in illegal drugs in the Philippines, citing severe consequences including extended detention while awaiting trial or long prison terms in facilities “far below UK standards.”

“Don’t become involved with drugs of any kind. Penalties for importing and using illegal drugs are particularly severe,” read the latest travel advice for the Philippines issued by the Foreign and Commonwealth Office (FCO).

The new travel advice came as deaths in police anti-drug operations or in what appeared to be rubout or vigilante killings continued to mount. Human rights groups have expressed alarm over the killings, saying they could be cases of summary executions of small time drug pushers or police assets.

President Duterte recently tagged five active and retired police officers as protectors of drug syndicates. Around 154,000 British nationals visited the Philippines in 2015.

The FCO also advised British nationals against travel to some parts of Mindanao and the Sulu archipelago because of clashes between the military and insurgent groups as well as possible terror attacks.

It cited an increase in cases of kidnapping of foreign nationals since late 2015.

“It’s likely that terrorist groups continue to plan kidnap operations against western nationals in the region. You should remain vigilant at all times,” the advisory read.

British nationals have also been warned about rampant street crimes especially robbery throughout the Philippines. They have also been urged to avoid large crowds and demonstrations and to follow the advice of local authorities.

The Bureau of Immigration in Manila has warned foreigners against taking part in political rallies. Getting caught in one would mean arrest or deportation or both, according to the BI.