RUBKONA, South Sudan — Sudanese warplanes bombed a market and an oil field in South Sudan on Monday, killing at least two people after Sudanese ground forces had reportedly crossed into South Sudan with tanks and artillery, elevating the risk of all-out war between the two old enemies.

The international community urged Sudan and South Sudan to talk out their disputes, which include arguments over where the border lies and over ownership of oil resources.

U.N. Secretary-General Ban Ki-moon condemned the Sudanese bombings and called on the government in Khartoum “to cease all hostilities immediately,” U.N. deputy spokesman Eduardo del Buey said.

Ban stressed again that the dispute cannot be solved militarily and urged Sudanese President Omar al-Bashir and South Sudan’s President Salva Kiir “to stop the slide towards further confrontation and … return to dialogue as a matter of urgency,” the spokesman said.

But al-Bashir vowed Monday to press ahead with his military campaign until all southern troops or affiliated forces are chased out of the north.

The bombs fell from two MiG 29 jets onto Rubkona’s market with a whistling sound, turning stalls where food and other household items are sold into fiery heaps of twisted metal. The burned body of a boy lay flat on his back near the center of the blast site, his hand clutching at the sky.

South Sudan military spokesman Col. Philip Aguer said two were killed in that attack and nine wounded.

Aguer said Antonov bombers accompanied by MiG 29 jets also bombed Abiemnom in Unity State and the Unity State oil field. He said Abiemnom is a two-hour drive from Rubkona.