— From wire reports

Building collapse arrest — Sean Benschop surrendered Saturday to face six counts of involuntary manslaughter, 13 counts of recklessly endangering another person and one count of risking a catastrophe in the Philadelphia building collapse case. A warrant had been issued for the 42-year-old and police had been searching for him. Six were killed and 13 injured in Wednesday’s collapse. Officials said a toxicology report showed evidence that Benschop was high on marijuana. Benschop’s attorney said his client was not at fault.

Zimmerman trial — Was it murder when George Zimmerman shot and killed Trayvon Martin? Or was it self-defense? That was the question 16 months ago, and it remains the question as potential jurors file into the Seminole County Courthouse in Sanford, Fla., on Monday at the start of Zimmerman’s trial on charges of second-degree murder. The case may come down to which version of events the jury finds more believable: Zimmerman’s assertion that he was attacked by Martin, or an account by a young woman who was talking to the victim on the phone moments before he was killed.

New Jersey — Cory Booker, who has built national celebrity from his perch as mayor of Newark, N.J., on Saturday officially declared his campaign for the U.S. Senate seat vacated by Sen. Frank Lautenberg’s death Monday. Booker, 44, enters the race heavily favored: Polls earlier in the year showed that he enjoyed far broader name recognition than any of his Democratic primary opponents. Gov. Chris Christie has declared the seat will be filled in a special election in mid-October with a primary little more than two months away.

More guards at Guantanamo — Two weeks after President Barack Obama pledged to appoint two special czars to work on closing the prison camps at Guantanamo Bay, Cuba, the jobs have yet to be filled — and the only jobs announced are in a plan to surge more troops to the detention center. On Saturday, 124 fresh guards from a military police company in Texas were scheduled to land at the remote base. It’s the vanguard of a plan to grow to 2,000 the staff at the prison camps, where 166 captives are being held.

Afghanistan deaths — Two U.S. soldiers and an American civilian working with them were killed in a so-called insider attack Saturday at a base in Afghanistan’s Paktika province. A soldier with the Afghan National Army opened fire during lunchtime, according to Afghan military officers. Last year, 48 insider attacks killed 64 international troops and civilians working with the military. In a second attack on international forces Saturday, an Italian soldier was killed.

Syrian rebels — The Syrian opposition will not attend the proposed conference on the crisis in Syria unless rebel fighters receive new supplies of arms, says Gen. Salim Idris, the top rebel commander. “If we don’t receive ammunition and weapons to change the position on the ground … very frankly I can say we will not go to Geneva.” Since Secretary of State John Kerry announced in May that the U.S. and Russia planned to organize a meeting, Syria has been strengthened by arms from Iran and the involvement of Hezbollah.

Drones in Pakistan — Just days after taking power, Pakistan’s new government summoned a top U.S. envoy Saturday to protest a U.S. drone strike, suggesting that Prime Minister Nawaz Sharif’s team fully intends to make good on its promise to aggressively push for an end to such strikes. Friday night’s drone strike near the Afghan border was said to have killed seven militants. Sharif wants to pursue peace talks with militants.

Chinese bus blast — An unemployed man intent on killing himself set off an explosion that engulfed a bus in flames and killed 47 in Xiamen, in southeastern China, on Friday, according to reports Saturday by state-run news organizations. The reports identified the man as Chen Shuizong, in his 60s and impoverished. He had written a suicide note in which he expressed deep frustration, said the reports, which were based on details of the investigation released by officials in Xiamen. Chen was believed to have died in the explosion.