(Adds criticism from firearms group, opposition)
By David Ljunggren
OTTAWA, March 20 (Reuters) - Canada's Liberal government unveiled proposals on Tuesday to tighten already tough gun control laws to address a spike in crimes involving firearms, including a deadly attack on a mosque last year.
The measures include enhanced background checks on people seeking to buy firearms, especially those with a history of violence. They also would oblige retailers to maintain adequate records of inventories and sales.
Although Canada has much stricter firearms restrictions than the United States, Ottawa says crimes involving guns rose 30 percent from 2013 to 2016. Gun homicides jumped 66 percent in the same period.
"Hard evidence shows a gun violence issue that is serious, getting worse, and not confined to big cities," Public Safety Minister Ralph Goodale told reporters when unveiling draft legislation that contained the proposals.
Six people died when a gunman attacked a Quebec City mosque last year. say that although Canada's gun laws ban dozens of assault rifles, some permitted firearms are easily modified for greater damage, and lax U.S. regulations make smuggled weapons accessible. Liberals promised last month to spend C$327.6 million ($250.4 million) over five years to tighten border security to block the illegal trafficking of guns and drugs.
The measures outlined on Tuesday could prompt voter anger against Liberal legislators in rural parliamentary constituencies who will face off against the official opposition Conservatives in the October 2019 election.
The National Firearms Association said it would campaign against what it called seriously misguided legislation.
"Firearms owners and users in Canada when motivated are a very strong political force," association president Sheldon Clare said in a statement.
Conservative public safety spokesman Pierre Paul-Hus said the measures "treat law-abiding firearms owners as criminals."
The Conservatives promise to resist attempts to recreate a federal registry of shotguns and rifles that was set up after a gunman killed 14 women in 1989.
The then-Conservative government abolished the registry in 2012, arguing it was wasteful and did nothing to cut crime.
Goodale said the government would not recreate the registry. Asked about possible electoral losses, he noted there had been extensive public consultations and added: "We think the balance we have stuck represents a good strong Canadian consensus."
Canadian gun owners must obtain licenses and go through safety training and extensive checks. A restricted class of guns must be registered for tracking, while fully automatic weapons are prohibited.
The AR-15 assault-style rifle, used in several recent U.S. massacres, is heavily restricted. Owners are subject to particularly thorough tests and verification measures, a government official told reporters on Tuesday.
($1 = 1.3083 Canadian dollars)