Bahrain Mirror-AP: In the small town of Diraz, just a few miles from where Prince Charles met with Bahrain's royals, there is graffiti demanding the death of the Gulf island's monarch, armored vehicles with chicken wire on their windows and a tense calm that could be shattered at any time.

The police have laid siege to the town for months, a sign of the lingering standoff between Bahrain's Shiite majority and its Sunni monarchy more than five years after Arab Spring protests were crushed. The ongoing crackdown has seen some activists imprisoned, others exiled, and a major Shiite opposition group dismantled.

But there was no sign of the unrest as Prince Charles and his wife Camilla took in the sights as part of a three-nation tour of the Gulf. The Prince of Wales inaugurated a new naval base on Thursday, the first permanent British military presence since its withdrawal from Bahrain in 1971.

The royal visit and the military base suggest Britain, which has long had influence with Bahrain's own monarchy, may not be pressing it on human rights. Tensions continue to grow amid the crackdown, with some worried a larger crisis could loom in Bahrain, which is home to the U.S. Navy's 5th Fleet.

"You will reach the level where people realize they have nothing left to lose," one local activist told The Associated Press.

Bahrain, a small island off the coast of the Arabian Peninsula, has long drawn revelers to bars across the causeway from dry Saudi Arabia. Its history as a port town for pearl divers and shippers has drawn an eclectic mix of Sunnis, Shiites, Iraqi Jews, Christian missionaries and Hindus.

The 2011 Arab Spring protests were backed by the Shiite majority and others, and were aimed at demanding more political freedoms from the ruling Al Khalifa family. The government put down the demonstrations with help from Saudi and Emirati troops, and later pledged to reform.

While low-level unrest persisted for years, things remained largely peaceful until April, when Bahrain's military announced it was "ready to deal firmly and with determination with these sedition groups and their heads" after a gasoline bomb killed a police officer.

Since then, authorities suspended the country's largest Shiite opposition group, Al-Wefaq, and doubled a prison sentence for its secretary-general, Sheikh Ali Salman. Famed activist Nabeel Rajab was imprisoned and now awaits sentencing on a charge of spreading "false news." Zainab al-Khawaja, the daughter of well-known activist Abdulhadi al-Khawaja, who himself is serving a life sentence over his role in the 2011 protests, was forced into exile.

The standoff in Diraz began in June, when supporters of Shiite cleric Sheikh Isa Qassim surrounded his home after the government revoked his citizenship.

Police now control entry to the town and film incoming local drivers, while Western expatriates blissfully jog past armored personnel carriers. Graffiti on nearby side streets demands "death" for King Hamad bin Isa Al Khalifa, while others show crude drawings of Pearl Square, the epicenter of the 2011 protests, which was later demolished by the government. Internet access cuts off nightly here, an outage researchers blame on government interference.

Bahrain has blamed its unrest partly on Shiite power Iran, though a government-sponsored investigation said there wasn't a "discernable link" between the 2011 demonstrations and Tehran based on the information the government gave them.

Posters throughout Bahraini highways show heavily armed SWAT teams from a Gulf-wide police exercise on the island, part of recent military maneuvers designed as a deterrent to Iran following last year's nuclear deal. Low oil prices have hurt the local economy, and forced Saudi Arabia to scale back its international aid.

Two activists who spoke Wednesday to the AP on condition of anonymity for fear of facing criminal charges said Bahrain's rulers were inflaming sectarian tension through their crackdown.

"They are betting on the silence of the West because of the supply of the facilities," one activist said, referring to the British and American bases. "They are compromising other things for this."

In a statement to AP, Bahrain's government said "no individual in Bahrain will, or can be, prosecuted for his or her political views due to the freedom of expression protections explicitly stated in the constitution," despite the cases to the contrary.

The British Foreign Office, while declining to address Prince Charles' private conversations, said United Kingdom officials have "frank discussions with the government of Bahrain about human rights concerns both in public and in private."

"We believe that it is not good enough to merely criticize other countries from the sidelines," the statement to the AP said. "Only by working with Bahrain are we able to bring about the changes we would like to see in the country."

However, even the day after the royals arrived, activists said prosecutors brought in several people for questioning likely ahead of filing criminal charges against them. Activists also offered a list of over 20 people recently put on a travel ban list, while independent news gathering grows more difficult.

On Thursday, Prince Charles traveled to the British Navy's new Mina Salman Support Facility, which the British Defense Ministry estimates will cost the U.K. at least 6.4 million pounds ($7.9 million), with Bahrain covering the rest. While there, Prince Charles visited the HMS Middletown docked at the base.