(CNN) -- A House subcommittee is expected to grill Department of Homeland Security officials about concerns that violence in Mexico may spill over the border into the United States.
Mexican federal police patrol last week on the streets of Ciudad Juarez, just across the border from El Paso, Texas.
Mexico's military and police have been embroiled in increasingly violent clashes with drug cartels, which are battling among themselves for control over an ever-growing market in the United States.
Rep. Loretta Sanchez, chairwoman of the House committee holding the hearing, said Thursday that what's happening in Mexico is becoming a growing problem for the United States.
"Well, it certainly has always been a problem at the border, but in the last couple of decades, it's gotten even worse. Now we see some spillover, just a little bit, coming into the United States," she said on CNN's "American Morning."
"I think it's time that we make a comprehensive plan to figure out, not just what we do about the violence at the border -- but it's all tied together with the economy down there, with our economy, ... commerce routes between the two countries."
The Border, Maritime and Global Counterterrorism Committee hearing on border issues focuses on violence and the transfer of guns from the United States to Mexico to arm the cartels.
Sanchez said it's a crime to sell some of the guns from stores within the United States and traffic them to Mexico. Most of the gun stores selling these weapons, she said, are within a mile of the U.S.-Mexico border.
Sanchez suggested looking at what types of guns are being sold in those stores and perhaps instituting some provision against assault weapons.
On Wednesday, Vice President Joe Biden talked about drug-related violence in Mexico.
"Since the beginning of last year, there have been nearly 7,000 drug-related murders in Mexico. If we had said that years ago, we would have looked at each other like we were crazy," he said. "Violent drug trafficking organizations are threatening both the United States and Mexican communities."
Biden made those remarks as he announced the nomination of Gil Kerlikowske as the new White House drug czar, a position that plays a key role in developing and implementing the Southwest border strategy.
Last year, more than 1,600 killings occurred in Juarez, three times more than the most murderous city in the United States. And last month, the city's chief of police was obliged to quit after threats from organized crime to kill a policeman every day that he remained on the job.
On Tuesday, five human heads were found in ice chests in the central Mexican state of Jalisco, police said. Growing drug violence has made beheadings in Tijuana, Juarez and other Mexican towns more commonplace over the past year.
In recent weeks, the United States, Canada, France, Italy and Germany have issued alerts about travel to Mexico.
"The situation in Ciudad Juarez is of special concern," the State Department said in an alert last month. "Mexican authorities report that more than 1,800 people have been killed in the city since January 2008. Additionally, this city of 1.6 million people experienced more than 17,000 car thefts and 1,650 carjackings in 2008."
Obama on Wednesday told regional newspaper reporters that he would consider sending the National Guard to the border if the situation escalated.
"We're going to examine whether and if National Guard deployments would make sense and under what circumstances they would make sense," Obama said, according to McClatchy Newspapers.
"I don't have a particular tipping point in mind," he told the reporters. "I think it's unacceptable if you've got drug gangs crossing our borders and killing U.S. citizens."
The president said he did not have any interest in "militarizing the border."
"We expect to have a comprehensive approach to dealing with these issues of border security that will involve supporting [Mexico President Felipe] Calderon and his efforts," Obama said, according to McClatchy. "Our expectation is to have a comprehensive policy in place in the next few months."
Obama and Joint Chiefs of Staff chairman Adm. Michael Mullen on Saturday discussed how the U.S. military can assist Mexico in addressing growing violence from drug cartels, according to a military official.
The president expressed interest in military capabilities that the U.S. has that could help Mexican forces, including intelligence, surveillance and reconnaissance technology, the official said.
CNN's Ismael Estrada, Kristi Keck, Rey Rodriguez and Barbara Starr contributed to this report.