A grim toll of a dozen fatalities in just three days marks the rapid onset of this year’s season of death along the US-Mexican border. As temperatures suddenly soared in southern Arizona this past week, so did border-crossing deaths.

Twelve border crossers were listed as dead in Arizona between last Friday and Monday. Border Patrol agents in western Arizona called this past weekend the busiest ever in a three-day period as they made forty rescues. An equal number were chalked up by agents in the Tucson sector.

Corpses of the crossers were scattered among different sectors of the border, with a majority found in the relatively unpopulated western part of the state. “What scares me is that there just continues to be very widely scattered deaths,” said the Rev. Robin Hoover, founder of Humane Borders, a group that puts out jugs of water in remote areas used by illegal crossers.

US border control policy over the past decade has increasingly funneled the immigrant flow into ever more rugged and dangerous terrain. More than 3,000 people have died trying to make the crossing in the past decade.

More than 200 extra Border Patrol agents were deployed in Arizona precisely to prevent such deaths this summer. Last year about 200 people died crossing the line in Arizona. An almost equal number perished in California and Texas.

This past weekend’s macabre tally comes as the national immigration debate simmers and as the first comprehensive immigration reform bill has been introduced in Congress.

The news of the border deaths this past weekend received minimal coverage, only a tiny fraction of the attention afforded last month to the shut-the-borders campaign staged by the Minuteman Project.

Just last week the Mexican Consulate undertook a public education campaign warning crossers that at this time of year they will face lethal conditions.