Swift action in the Republican-controlled statehouse, where the National Rifle Association (NRA) has long held sway, was propelled in large part by the extraordinary lobbying efforts of young survivors from the massacre three weeks ago at Marjory Stoneman Douglas High School in Parkland.

But the legislation, while containing a number of provisions student activists and their parents from Parkland, Florida, had embraced, left out one of their chief demands - a ban on assault-style weapons like the one used in the Feb. 14 rampage.

The bill overcame strenuous objections to provisions permitting school staff to carry guns on the job. Critics say that will pose a particular risk to minority students, who they say are more likely to be shot in the heat of a disciplinary situation or if mistaken as an intruder.

Still, a group of families of victims and survivors of the shooting applauded the legislation's passage in a message posted on Twitter by parent Ryan Petty, whose daughter was among those killed, and urged Republican Governor Rick Scott to sign it.

The measure will automatically become law within 15 days unless vetoed by Scott, who said on Wednesday prior to the vote that he had not yet decided whether to support the bill.

The bill's passage signaled a possible turning point in the national debate between gun control advocates and proponents of firearms rights enshrined in the Second Amendment of the U.S. Constitution.

The measure narrowly cleared the state Senate on Monday before passing in the House of Representatives on Wednesday in a 67-50 vote. Ten House Democrats joined 57 Republicans in supporting the bill, while 19 Republicans and 31 Democrats voted against it.

As legislators debated in Tallahassee, U.S. Education Secretary Betsy DeVos visited Stoneman Douglas on the first full day of classes since the shooting, while the accused gunman, Nikolas Cruz, was indicted on 17 counts of murder.

SCHOOLHOUSE "GUARDIANS"

The action by Florida's lawmakers represented both a break with the NRA on gun sale restrictions and a partial acceptance of its proposition that the best defense against armed criminals is the presence of "good guys with guns."

The bill would create a program allowing local sheriffs to deputize school staff as volunteer armed "guardians," subject to special training, mental health and drug screening and a license to carry a concealed weapon. Each school district would decide whether to opt in.

Nearly all classroom teachers are expressly excluded from participating in a compromise aimed at winning support from some Democrats and Scott, a staunch NRA ally who nevertheless is opposed to arming teachers. Otherwise, only non-teacher personnel are eligible, such as administrators, guidance counselors, librarians and coaches.

Florida would join at least six other states - Georgia, Kansas, South Dakota, Tennessee, Texas and Wyoming - with laws allowing school employees to carry firearms in public schools, according to the National Conference of State Legislatures.

President Donald Trump has voiced support for arming teachers as a deterrent to school gun violence, though many parents, law enforcement officials and policymakers in both parties reject the idea.

"The thought of even one student being gunned down by the person responsible for educating and caring for them is just too much," Representative Amy Mercado, a Democrat from Orlando, said during the House floor debate.

She and critics decried the lack of an assault weapons ban in the bill, though supporters noted that most school shootings in the United States are committed with handguns.

The online statement Petty posted on behalf of victims' loved ones said: "We know that when it comes to preventing future acts of school violence, today's vote is just the beginning of our journey."

Scott told reporters he would "review the bill line by line" and consult with victims' families before deciding his position.

Besides his objections to arming teachers, Scott is on record as opposed to extending Florida's existing three-day waiting period for handgun sales to purchases of all firearms.

The bill would also raise the legal age for all gun purchases to 21. The minimum age for handguns nationally is 21, but a person as young as 18 can buy a rifle in Florida.

Cruz was 18 years old when he legally purchased the semiautomatic AR-15 assault-style rifle used in the Stoneman Douglas massacre, according to authorities.

The measure also allows police to temporarily seize guns from anyone been taken into custody for an involuntary mental examination and to seek a court order barring a person from possessing firearms if that individual is deemed dangerous because of a mental illness or violent behavior.

Cruz had a history of mental issues, numerous encounters with police and was expelled from Stoneman Douglas last year for disciplinary problems, according to authorities.