Arrests made in Mexico grenade attack raise questions

The attorney general’s office announced Friday afternoon that it arrested three men in connection with the two grenade explosions in Morelia, Michoacan, last week that killed 8 people and left more than a hundred injured.
According to a statement from Asst. Atty. Gen. Maricela Morales Ibañez, the suspects were arrested in the town of Apatzingan, Michoacan, after an anonymous tip.
Authorities said Julio César Mondragón Morales, Juan Carlos Castro Galeana and Alfredo Rosas Elisea had confessed to having detonated the grenades during Independence Day festivities on Sept. 15. Officials identified the men as members of a brutal drug gang known as the Zetas.
El Universal, reporting from the press conference where the statement was made, said one of the detainees, Rosas Elisea, appeared to have been beaten.
Tracy Wikinson filed this report for the LATimes this morning:

Slumped at an interrogation table, a gang member accused of participating in an attack that killed eight people at an Independence Day celebration described calmly how he was eager to get rid of the grenade he tossed into a crowded plaza.
“I was hiding it in my hands and it made me shudder,” Juan Carlos Castro Galeana told his interrogator. “I was desperate to get rid of it.”
Castro added that he thought the attack, which he said he was ordered to carry out, was meant to “provoke” the government. He appears in a video posted Saturday on the website of El Universal newspaper. The video was obtained from the attorney general’s office, the newspaper said.

The arrests pose as many questions as they provide answers. How do three men throw two grenades? If these guys are soldiers – or the highly trained hit men that Los Zetas are rumoured to be – then why do they look like the average man off the street rather than trained killing machines? Or were they just hired by the Zetas to do their gruesome bidding? And physical bruising visible on some of the suspects suggest that confessions might have been extracted under questionable circumstances.