MANAMA In the rubbish-strewn streets of Sanabis, the police are on the prowl for the culprits.
A group of Shi'ite teenagers and women, some of them mothers, some of them single, scuttle into a nearby house, putting out the lights as men get out of cars and drag some boys down from a rooftop across the street.
The incriminating item is hurriedly stuffed down the back of a sofa, letting out a small noise which threatens for a few seconds to give the game away. But the danger passes. The police move on and the small plastic bugle is whipped out once more.
The vuvuzela -- used here to pipe out the phrase "Down with Hamad," Bahrain's king -- has become one of the mundane props in a game of brinkmanship between the Sunni Muslim ruling elite and majority Shi'ites who see confirmation in the daily clashes with police that they are oppressed.
"All people are doing is shouting slogans or using a bugle. But police are entering people's houses and arresting them," says one of the women, an unmarried government employee.
Bahrain has been in turmoil since pro-democracy protests, inspired by revolts in Egypt and Tunisia, took to the streets in February.
But a fight that started as an attempt to foster the Gulf region's first real democracy now often looks more like a sectarian conflict between Sunni and Shi'ite, as well as a power struggle between the two powers who seek to champion them -- Saudi Arabia and Iran.
The government invited Sunni neighbor Saudi Arabia to send troops to help crush the movement in March, saying the mostly Shi'ite protesters had sectarian motives and backing from Iran, but the island state has remained tense ever since.
Around 30 people died during the disturbances earlier this year, mostly Shi'ites protesters but also some police and Asian expatriates, but the figure has risen to around 40 in ongoing clashes in Shi'ite villages as government measures to calm the situation fall flat.
By-elections were held last week to fill parliamentary seats vacated by the leading opposition group, the Shi'ite-based Wefaq party, after security forces first killed activists in February, but a Wefaq boycott managed to embarrass the authorities.
Only 17 percent of eligible voters cast ballots, effectively ruining government efforts to delegitimize Wefaq as the main voice of the Shi'ite electorate who demand ceding real powers to parliament and removal of a prime minister -- an uncle of the king -- who has been there for four decades.
The women in Sanabis, a lower-middle-class suburb of the capital that has developed into one of the strongholds of anti-government feeling, say there can be no compromise with a government that looks down on them as rural Shi'ites of second-class status.
"The government has to go, the crimes are too big now. Through continuous revolution, we cannot stop and cannot surrender," says Fatima, a mother of one.
Most Shi'ites look to Bahrain's most senior Shi'ite cleric Issa Qassem for guidance in religious affairs, though others may follow clerics in Iraq, Lebanon or Iran.
In this home, where the women take refuge from the police, a small frayed sticker of Iranian leader Ayatollah Ali Khamenei sits above a door. Iran once sought to inspire Shi'ites with its 1979 revolution, but its ability to impress has faded.
"Most Sunnis are afraid because the government tries to show them we belong to Iran, so they don't support us," says Umm Haidar, denying claims that clerics abroad give them orders. "We follow them on religion, not politics."
Sunnis, who tend to reside in the more affluent areas around Manama, view things through an entirely different lens.
Saud, a young IT lecturer at a private university who did not want to be identified by his full name, says Wefaq and most Shi'ites want an Islamic republic and they are escalating violence against security forces to get it. He denies that Sunnis are the minority.
Gullible foreign powers such as the United States are helping them, he said, evidenced by U.S. President Barack Obama citing Wefaq in a recent U.N. speech.
Secular opposition parties, such as Waad, led by Sunni politician Ibrahim Sharif, were misled into joining with Wefaq in demands for democracy, he said, talking in a hotel of the upscale Juffair neighborhood.
"Wefaq doesn't issue statements condemning violence. Every single night there are policemen injured by rocks, buckets of paint are thrown on them and they face Molotov cocktails," he says. "If they don't condemn, that means they agree. Is Wefaq trying to ignite sectarian war by ignoring this?
"People on the ground are asking for reforms, but how about reforming their actions, their minds, their beliefs? Change starts at the individual level."
He recalled how he found his students separating out into Sunni on one side and Shi'ites on the other at one stage in March, though things have returned now to normal.
"This is a lovely country and it really doesn't deserve what's happening to it," he said.
With entrenched views like these now dominating Sunni and Shi'ite thinking, Bahrain seems headed for more communal strife.
Shi'ites who voted in the by-election and rejected Wefaq say they are witnessing radicalization in Shi'ite villages.
"People in the streets want someone to hear them and say at least 'we want to speak to you'. We in villages see these things happening every night and it's spreading to areas where nothing used to happen," said Isa Mohammed, who works in corporate communications, citing clashes in Malkiya.
"What is happening now is like mass punishment. The police come in big numbers and rain villages with teargas and that's attracting many others who are not close to this," he said, adding his father's home was recently damaged by police actions.
One of the main gripes was dismissals of Shi'ites from many companies for taking part in the protests, Mohammed said. King Hamad promised many would get their jobs back but his orders had not been fully implemented, he said, hinting at disputes inside the ruling Al Khalifa family over how to proceed.
Michael Stephens, a Royal United Services Institute (RUSI) researcher based in Qatar, said the king -- facing a Shi'ite street demanding more reforms and Sunni hardliners demanding no compromises -- needed to take action to stop the escalating violence.
"We've reached the point where the regime knows it can't afford more dead people on its hands, so it will use detention and teargas," Stephens said. "The king has to come forward and show strength."
(Editing by Sonya Hepinstall)