At least 30 killed in Yemen, raising fears of a broader conflict

(Yemen is the red/black area below Saudia Arabia and to the west of Oman, just above Somalia. To the southwest of Yemen is the Red Sea, to the south east, the Gulf of Aden, where most of the Somalian Piracy, to date, has taken place.
Christian Science Monitor: At least 30 killed in Yemen, raising fears of a broader conflict
Sanaa, Yemen

At least 30 were killed in Yemen Friday as government loyalists opened fire on opposition demonstrators gathered at Sanaa University, according to medical workers at the scene.

Just after Friday prayers, men armed with semiautomatic weapons began firing on protesters from rooftops of buildings overlooking the area. Massive clouds of black smoke could be seen billowing from the edge of the demonstration area.

“As soon as we got up from prayer they started firing from the tops of multiple buildings in the area,” said Essam al-Maqtary, a Sanaa resident who was shot in the leg. “The baltageya [thugs] lit tires on fire so nobody could see exactly where they were and so they couldn’t be recorded on video.”

The intensification of force used against demonstrators has some concerned that protesters will retaliate, threatening the possibility of a broad war that could engulf the country. Yemen is the second most heavily armed country in the world, behind the US.

Yemen is the second most heavily armed country in the world? What does that mean? Are they saying their people have hand guns, like a lot of Americans do?