MONTERREY, Mexico (AFP) - US Secretary of State Hillary Clinton on Thursday urged young Mexicans to push for more democratic reforms and to fight corruption as she broadened a campaign against drug gangs.

Wrapping up a two-day visit to Mexico in which she stressed both the United States and its southern neighbor shared blame for the scourge, Clinton brought her campaign to a high-tech university in Monterrey, some 100 miles (160 kilometers) from the US border.

Clinton told students at Universidad TecMilenio that she had fruitful discussions with Mexican leaders and that she hoped the "judicial and police reforms passed in recent months will come into full fruition."

But in a speech at the university's campus, nestled on green hillsides, she said the burden for change lay beyond government officials, generals and police officers and also fell on business leaders and academics, among others.

"It's particularly important for the young people in Mexico, who have enormous power right now, to strengthen your democracy, to call for more reforms, to shine a bright light on corruption wherever you might see it," Clinton said.

"Mexican young people can be a transformative force at this critical juncture in your country's history and I urge you to seize this moment and join your voices in this struggle."

In its latest country reports on narcotics, the State Department cited official corruption as a major stumbling block to fighting the drug cartels that have plunged the country in bloodshed.

But reform was not enough, Clinton added.

"When one thinks about how important it is to tackle corruption and drugs ... progress can only take hold if it is built on the foundation of economic growth and material improvement in people's daily lives," she said.

"We must demonstrate unequivocally that democracy produces positive outcomes" for people who work hard, she added.

In response to a question from a Mexican journalist, Clinton later suggested that President Barack Obama's administration might change plans to build a border wall begun under president George W. Bush.

"There have been lots of legitimate concerns about the border wall," Clinton told reporters at the same university.

"In some parts of our border which are so desolate and isolated it might very well make sense, but in many places that it was mooted by the Bush administration, we don't think it matters.

"So we are taking a hard look at that and trying to figure out what works and what doesn't," the chief US diplomat said.

Earlier in Mexico City, Clinton toured the federal police's state-of-the art headquarters, a key command center in the country's bloody war on its drug cartels.

Mexico's top federal police officer, Genaro Garcia Luna, escorted Clinton around the site in southwest Mexico City, showing how the country, with US support, is building a modern police force capable of taking on organized crime.

Garcia Luna showed off US-built Blackhawk helicopters used to battle drug cartels, then accompanied Clinton in watching a police hostage rescue exercise on a disabled passenger airplane.

The drug war have left 6,300 people dead in Mexico since early 2008, with violence spilling over its northern border into the United States in the form of kidnappings.

Mexico has long complained its police force is often outgunned by drug dealers armed with firearms purchased in the United States and smuggled into the country.

In an interview with NBC television late Wednesday, Clinton called letting a previous US ban on the sale of assault weapons expire "a mistake."

"So we will make the case that we need to put more teeth in the law, try to prohibit the sale outside of our borders of these guns," she said.

But she acknowledged that a move to renew the ban would draw strong opposition in Congress.

Clinton also visited the Basilica of Guadalupe, one of the most important religious shrines in the Americas.

The site is visited by millions of pious Catholics each year.

On Wednesday, Clinton said Washington would stand by Mexico in its fight against drug cartels, acknowledging that the United States needed to do more to halt the flow of arms and drug profits south to Mexico.

She also said the United States had to focus on dulling "the insatiable" demand for illegal drugs north of Mexico's border.

Analysts say the Obama strategy represents a break from the Bush administration, which offered to help Mexico fight the violence despite largely viewing it as a Mexican problem.

Clinton announced Washington would give Mexico 80 million dollars to buy US-made Blackhawk helicopters to bolster its armory against drug traffickers who control most of South America's multi-billion-dollar cocaine trade.

By Lachlan Carmichael, AFP, March 26, 2009