Mexican security forces have killed seven more members of a presumed cartel assault force, a day after after clashing with a group of heavily armed gang members.

Four officers died and six were wounded in the hourlong confrontation on Saturday in the northern town of Villa Union, about 65 kilometers (40 miles) from the US border.

The group reportedly entered the town of 3,000 inhabitants in a convoy of pickup trucks before storming local government buildings at around midday.

Read more: Mexico auctions drug lords' properties, raises $2.9 million

Speaking outside the bullet-riddled town mayor's office, Governor Miguel Angel Riquelme told reporters the state had acted "decisively" to repel the gunmen. He said they were members of the Cartel of the Northeast, which is from the neighboring state of Tamaulipas.

A number of municipal workers were missing, he added.

Record murder rate

The violence comes as Mexican President Andres Manuel Lopez Obrador marks one year in office. He was elected in 2018 on a promise to tackle gang-related crime and has come under mounting pressure after a series of recent attacks.

Three women with US citizenship and six of their children were killed in a drug cartel ambush last month in northern Mexico.

Read more: When drug violence 'turns into terrorism'

The country's murder rate has risen to record levels — federal officials say there have been 29,414 homicides so far in 2019, compared to 28,869 in the same period of 2018.

es, nm/cmk (Reuters, AFP, AP)

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