The Rwandan fovernment has accused the Democratic Republic of Congo of bombing the country, killing a woman and injuring her baby.
The DRC has denied the accusations, blaming rebels, who are purported to be backed by Rwanda, according to the DRC and the UN.
"Rwandan civilians are being targeted by DRC forces. We have remained restrained for as long as we can but this provocation can no longer be tolerated," said Foreign Minister Louise Mushikiwabo.
"We have the capacity to determine who fired at us and will not hesitate to defend our territory."
DRC and UN forces have been attacking M23 rebel positions near the border with Rwanda, with fighting reported to have left at least 80 people dead since last week.