NEAR ELSA - Sheriff's deputies said an autopsy will reveal the gender and how long a body had been decomposing before it was discovered by people fishing in an irrigation canal Sunday afternoon.

The murder investigation is the 21st for the Hidalgo County Sheriff's Office in 2008 - "by far ... the deadliest year" since Sheriff Lupe Treviño took office in 2005.

Authorities said a family fishing in the canal discovered the body wrapped in a tarp, tied with a rope and weighed down by a cinder block in the water. The body was found near the intersection of Farm to Market 88 and Mile 19 North roads at about 2:35 p.m. Sunday.

Treviño said in a news release that the body was "badly decomposed" and partially sunk in the water. An autopsy was ordered to find out how the person died, how long the body had been decomposing and to find out the person's identity and gender, deputies said.

No identification was found on the body.

"Once sex is determined, that will give us a lead into which missing persons report to follow up on," the sheriff's release reads.

Along with a deadly shooting in Monte Alto on Friday, the Hidalgo County Sheriff's Office has embarked on its 20th and 21st murder investigations of the year. Of those, 18 have been solved, Sheriff Lupe Treviño said.

There were 16 homicides by the sheriff's office in 2006 and 14 reports in 2007, according to The Monitor archives.

While this is, perhaps, the deadliest year on history for the sheriff's office, only two of the solved murders happened between people who did not already know each other, Treviño said.

"Stranger-on-stranger murders are extremely rare," Treviño said. "You're more likely to get murdered by your spouse or family member or an associate than a stranger.

"Hidalgo County still remains to be a relatively safe county to live, to work and to study in."

Jared Taylor covers law enforcement and general assignments for The Monitor. You can reach him at (956) 683-4439.